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@kwote kwote commented Jul 2, 2017

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@kwote kwote closed this Jul 2, 2017
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kwote commented Jul 2, 2017

I'm sorry, this was made by mistake.

torvalds pushed a commit that referenced this pull request Sep 27, 2019
We got a null pointer deference BUG_ON in blk_mq_rq_timed_out()
as following:

[  108.825472] BUG: kernel NULL pointer dereference, address: 0000000000000040
[  108.827059] PGD 0 P4D 0
[  108.827313] Oops: 0000 [#1] SMP PTI
[  108.827657] CPU: 6 PID: 198 Comm: kworker/6:1H Not tainted 5.3.0-rc8+ #431
[  108.829503] Workqueue: kblockd blk_mq_timeout_work
[  108.829913] RIP: 0010:blk_mq_check_expired+0x258/0x330
[  108.838191] Call Trace:
[  108.838406]  bt_iter+0x74/0x80
[  108.838665]  blk_mq_queue_tag_busy_iter+0x204/0x450
[  108.839074]  ? __switch_to_asm+0x34/0x70
[  108.839405]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.839823]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.840273]  ? syscall_return_via_sysret+0xf/0x7f
[  108.840732]  blk_mq_timeout_work+0x74/0x200
[  108.841151]  process_one_work+0x297/0x680
[  108.841550]  worker_thread+0x29c/0x6f0
[  108.841926]  ? rescuer_thread+0x580/0x580
[  108.842344]  kthread+0x16a/0x1a0
[  108.842666]  ? kthread_flush_work+0x170/0x170
[  108.843100]  ret_from_fork+0x35/0x40

The bug is caused by the race between timeout handle and completion for
flush request.

When timeout handle function blk_mq_rq_timed_out() try to read
'req->q->mq_ops', the 'req' have completed and reinitiated by next
flush request, which would call blk_rq_init() to clear 'req' as 0.

After commit 12f5b93 ("blk-mq: Remove generation seqeunce"),
normal requests lifetime are protected by refcount. Until 'rq->ref'
drop to zero, the request can really be free. Thus, these requests
cannot been reused before timeout handle finish.

However, flush request has defined .end_io and rq->end_io() is still
called even if 'rq->ref' doesn't drop to zero. After that, the 'flush_rq'
can be reused by the next flush request handle, resulting in null
pointer deference BUG ON.

We fix this problem by covering flush request with 'rq->ref'.
If the refcount is not zero, flush_end_io() return and wait the
last holder recall it. To record the request status, we add a new
entry 'rq_status', which will be used in flush_end_io().

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: stable@vger.kernel.org # v4.18+
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>

-------
v2:
 - move rq_status from struct request to struct blk_flush_queue
v3:
 - remove unnecessary '{}' pair.
v4:
 - let spinlock to protect 'fq->rq_status'
v5:
 - move rq_status after flush_running_idx member of struct blk_flush_queue
Signed-off-by: Jens Axboe <axboe@kernel.dk>
anlaneg pushed a commit to anlaneg/linux that referenced this pull request Oct 3, 2019
We got a null pointer deference BUG_ON in blk_mq_rq_timed_out()
as following:

[  108.825472] BUG: kernel NULL pointer dereference, address: 0000000000000040
[  108.827059] PGD 0 P4D 0
[  108.827313] Oops: 0000 [#1] SMP PTI
[  108.827657] CPU: 6 PID: 198 Comm: kworker/6:1H Not tainted 5.3.0-rc8+ torvalds#431
[  108.829503] Workqueue: kblockd blk_mq_timeout_work
[  108.829913] RIP: 0010:blk_mq_check_expired+0x258/0x330
[  108.838191] Call Trace:
[  108.838406]  bt_iter+0x74/0x80
[  108.838665]  blk_mq_queue_tag_busy_iter+0x204/0x450
[  108.839074]  ? __switch_to_asm+0x34/0x70
[  108.839405]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.839823]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.840273]  ? syscall_return_via_sysret+0xf/0x7f
[  108.840732]  blk_mq_timeout_work+0x74/0x200
[  108.841151]  process_one_work+0x297/0x680
[  108.841550]  worker_thread+0x29c/0x6f0
[  108.841926]  ? rescuer_thread+0x580/0x580
[  108.842344]  kthread+0x16a/0x1a0
[  108.842666]  ? kthread_flush_work+0x170/0x170
[  108.843100]  ret_from_fork+0x35/0x40

The bug is caused by the race between timeout handle and completion for
flush request.

When timeout handle function blk_mq_rq_timed_out() try to read
'req->q->mq_ops', the 'req' have completed and reinitiated by next
flush request, which would call blk_rq_init() to clear 'req' as 0.

After commit 12f5b93 ("blk-mq: Remove generation seqeunce"),
normal requests lifetime are protected by refcount. Until 'rq->ref'
drop to zero, the request can really be free. Thus, these requests
cannot been reused before timeout handle finish.

However, flush request has defined .end_io and rq->end_io() is still
called even if 'rq->ref' doesn't drop to zero. After that, the 'flush_rq'
can be reused by the next flush request handle, resulting in null
pointer deference BUG ON.

We fix this problem by covering flush request with 'rq->ref'.
If the refcount is not zero, flush_end_io() return and wait the
last holder recall it. To record the request status, we add a new
entry 'rq_status', which will be used in flush_end_io().

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: stable@vger.kernel.org # v4.18+
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>

-------
v2:
 - move rq_status from struct request to struct blk_flush_queue
v3:
 - remove unnecessary '{}' pair.
v4:
 - let spinlock to protect 'fq->rq_status'
v5:
 - move rq_status after flush_running_idx member of struct blk_flush_queue
Signed-off-by: Jens Axboe <axboe@kernel.dk>
mrchapp pushed a commit to mrchapp/linux that referenced this pull request Oct 4, 2019
commit 8d69966 upstream.

We got a null pointer deference BUG_ON in blk_mq_rq_timed_out()
as following:

[  108.825472] BUG: kernel NULL pointer dereference, address: 0000000000000040
[  108.827059] PGD 0 P4D 0
[  108.827313] Oops: 0000 [#1] SMP PTI
[  108.827657] CPU: 6 PID: 198 Comm: kworker/6:1H Not tainted 5.3.0-rc8+ torvalds#431
[  108.829503] Workqueue: kblockd blk_mq_timeout_work
[  108.829913] RIP: 0010:blk_mq_check_expired+0x258/0x330
[  108.838191] Call Trace:
[  108.838406]  bt_iter+0x74/0x80
[  108.838665]  blk_mq_queue_tag_busy_iter+0x204/0x450
[  108.839074]  ? __switch_to_asm+0x34/0x70
[  108.839405]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.839823]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.840273]  ? syscall_return_via_sysret+0xf/0x7f
[  108.840732]  blk_mq_timeout_work+0x74/0x200
[  108.841151]  process_one_work+0x297/0x680
[  108.841550]  worker_thread+0x29c/0x6f0
[  108.841926]  ? rescuer_thread+0x580/0x580
[  108.842344]  kthread+0x16a/0x1a0
[  108.842666]  ? kthread_flush_work+0x170/0x170
[  108.843100]  ret_from_fork+0x35/0x40

The bug is caused by the race between timeout handle and completion for
flush request.

When timeout handle function blk_mq_rq_timed_out() try to read
'req->q->mq_ops', the 'req' have completed and reinitiated by next
flush request, which would call blk_rq_init() to clear 'req' as 0.

After commit 12f5b93 ("blk-mq: Remove generation seqeunce"),
normal requests lifetime are protected by refcount. Until 'rq->ref'
drop to zero, the request can really be free. Thus, these requests
cannot been reused before timeout handle finish.

However, flush request has defined .end_io and rq->end_io() is still
called even if 'rq->ref' doesn't drop to zero. After that, the 'flush_rq'
can be reused by the next flush request handle, resulting in null
pointer deference BUG ON.

We fix this problem by covering flush request with 'rq->ref'.
If the refcount is not zero, flush_end_io() return and wait the
last holder recall it. To record the request status, we add a new
entry 'rq_status', which will be used in flush_end_io().

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: stable@vger.kernel.org # v4.18+
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

-------
v2:
 - move rq_status from struct request to struct blk_flush_queue
v3:
 - remove unnecessary '{}' pair.
v4:
 - let spinlock to protect 'fq->rq_status'
v5:
 - move rq_status after flush_running_idx member of struct blk_flush_queue
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Noltari pushed a commit to Noltari/linux that referenced this pull request Oct 5, 2019
commit 8d69966 upstream.

We got a null pointer deference BUG_ON in blk_mq_rq_timed_out()
as following:

[  108.825472] BUG: kernel NULL pointer dereference, address: 0000000000000040
[  108.827059] PGD 0 P4D 0
[  108.827313] Oops: 0000 [#1] SMP PTI
[  108.827657] CPU: 6 PID: 198 Comm: kworker/6:1H Not tainted 5.3.0-rc8+ torvalds#431
[  108.829503] Workqueue: kblockd blk_mq_timeout_work
[  108.829913] RIP: 0010:blk_mq_check_expired+0x258/0x330
[  108.838191] Call Trace:
[  108.838406]  bt_iter+0x74/0x80
[  108.838665]  blk_mq_queue_tag_busy_iter+0x204/0x450
[  108.839074]  ? __switch_to_asm+0x34/0x70
[  108.839405]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.839823]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.840273]  ? syscall_return_via_sysret+0xf/0x7f
[  108.840732]  blk_mq_timeout_work+0x74/0x200
[  108.841151]  process_one_work+0x297/0x680
[  108.841550]  worker_thread+0x29c/0x6f0
[  108.841926]  ? rescuer_thread+0x580/0x580
[  108.842344]  kthread+0x16a/0x1a0
[  108.842666]  ? kthread_flush_work+0x170/0x170
[  108.843100]  ret_from_fork+0x35/0x40

The bug is caused by the race between timeout handle and completion for
flush request.

When timeout handle function blk_mq_rq_timed_out() try to read
'req->q->mq_ops', the 'req' have completed and reinitiated by next
flush request, which would call blk_rq_init() to clear 'req' as 0.

After commit 12f5b93 ("blk-mq: Remove generation seqeunce"),
normal requests lifetime are protected by refcount. Until 'rq->ref'
drop to zero, the request can really be free. Thus, these requests
cannot been reused before timeout handle finish.

However, flush request has defined .end_io and rq->end_io() is still
called even if 'rq->ref' doesn't drop to zero. After that, the 'flush_rq'
can be reused by the next flush request handle, resulting in null
pointer deference BUG ON.

We fix this problem by covering flush request with 'rq->ref'.
If the refcount is not zero, flush_end_io() return and wait the
last holder recall it. To record the request status, we add a new
entry 'rq_status', which will be used in flush_end_io().

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: stable@vger.kernel.org # v4.18+
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

-------
v2:
 - move rq_status from struct request to struct blk_flush_queue
v3:
 - remove unnecessary '{}' pair.
v4:
 - let spinlock to protect 'fq->rq_status'
v5:
 - move rq_status after flush_running_idx member of struct blk_flush_queue
Signed-off-by: Jens Axboe <axboe@kernel.dk>
heftig pushed a commit to zen-kernel/zen-kernel that referenced this pull request Oct 5, 2019
commit 8d69966 upstream.

We got a null pointer deference BUG_ON in blk_mq_rq_timed_out()
as following:

[  108.825472] BUG: kernel NULL pointer dereference, address: 0000000000000040
[  108.827059] PGD 0 P4D 0
[  108.827313] Oops: 0000 [#1] SMP PTI
[  108.827657] CPU: 6 PID: 198 Comm: kworker/6:1H Not tainted 5.3.0-rc8+ torvalds#431
[  108.829503] Workqueue: kblockd blk_mq_timeout_work
[  108.829913] RIP: 0010:blk_mq_check_expired+0x258/0x330
[  108.838191] Call Trace:
[  108.838406]  bt_iter+0x74/0x80
[  108.838665]  blk_mq_queue_tag_busy_iter+0x204/0x450
[  108.839074]  ? __switch_to_asm+0x34/0x70
[  108.839405]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.839823]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.840273]  ? syscall_return_via_sysret+0xf/0x7f
[  108.840732]  blk_mq_timeout_work+0x74/0x200
[  108.841151]  process_one_work+0x297/0x680
[  108.841550]  worker_thread+0x29c/0x6f0
[  108.841926]  ? rescuer_thread+0x580/0x580
[  108.842344]  kthread+0x16a/0x1a0
[  108.842666]  ? kthread_flush_work+0x170/0x170
[  108.843100]  ret_from_fork+0x35/0x40

The bug is caused by the race between timeout handle and completion for
flush request.

When timeout handle function blk_mq_rq_timed_out() try to read
'req->q->mq_ops', the 'req' have completed and reinitiated by next
flush request, which would call blk_rq_init() to clear 'req' as 0.

After commit 12f5b93 ("blk-mq: Remove generation seqeunce"),
normal requests lifetime are protected by refcount. Until 'rq->ref'
drop to zero, the request can really be free. Thus, these requests
cannot been reused before timeout handle finish.

However, flush request has defined .end_io and rq->end_io() is still
called even if 'rq->ref' doesn't drop to zero. After that, the 'flush_rq'
can be reused by the next flush request handle, resulting in null
pointer deference BUG ON.

We fix this problem by covering flush request with 'rq->ref'.
If the refcount is not zero, flush_end_io() return and wait the
last holder recall it. To record the request status, we add a new
entry 'rq_status', which will be used in flush_end_io().

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: stable@vger.kernel.org # v4.18+
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

-------
v2:
 - move rq_status from struct request to struct blk_flush_queue
v3:
 - remove unnecessary '{}' pair.
v4:
 - let spinlock to protect 'fq->rq_status'
v5:
 - move rq_status after flush_running_idx member of struct blk_flush_queue
Signed-off-by: Jens Axboe <axboe@kernel.dk>
damentz pushed a commit to zen-kernel/zen-kernel that referenced this pull request Oct 5, 2019
commit 8d69966 upstream.

We got a null pointer deference BUG_ON in blk_mq_rq_timed_out()
as following:

[  108.825472] BUG: kernel NULL pointer dereference, address: 0000000000000040
[  108.827059] PGD 0 P4D 0
[  108.827313] Oops: 0000 [#1] SMP PTI
[  108.827657] CPU: 6 PID: 198 Comm: kworker/6:1H Not tainted 5.3.0-rc8+ torvalds#431
[  108.829503] Workqueue: kblockd blk_mq_timeout_work
[  108.829913] RIP: 0010:blk_mq_check_expired+0x258/0x330
[  108.838191] Call Trace:
[  108.838406]  bt_iter+0x74/0x80
[  108.838665]  blk_mq_queue_tag_busy_iter+0x204/0x450
[  108.839074]  ? __switch_to_asm+0x34/0x70
[  108.839405]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.839823]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.840273]  ? syscall_return_via_sysret+0xf/0x7f
[  108.840732]  blk_mq_timeout_work+0x74/0x200
[  108.841151]  process_one_work+0x297/0x680
[  108.841550]  worker_thread+0x29c/0x6f0
[  108.841926]  ? rescuer_thread+0x580/0x580
[  108.842344]  kthread+0x16a/0x1a0
[  108.842666]  ? kthread_flush_work+0x170/0x170
[  108.843100]  ret_from_fork+0x35/0x40

The bug is caused by the race between timeout handle and completion for
flush request.

When timeout handle function blk_mq_rq_timed_out() try to read
'req->q->mq_ops', the 'req' have completed and reinitiated by next
flush request, which would call blk_rq_init() to clear 'req' as 0.

After commit 12f5b93 ("blk-mq: Remove generation seqeunce"),
normal requests lifetime are protected by refcount. Until 'rq->ref'
drop to zero, the request can really be free. Thus, these requests
cannot been reused before timeout handle finish.

However, flush request has defined .end_io and rq->end_io() is still
called even if 'rq->ref' doesn't drop to zero. After that, the 'flush_rq'
can be reused by the next flush request handle, resulting in null
pointer deference BUG ON.

We fix this problem by covering flush request with 'rq->ref'.
If the refcount is not zero, flush_end_io() return and wait the
last holder recall it. To record the request status, we add a new
entry 'rq_status', which will be used in flush_end_io().

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: stable@vger.kernel.org # v4.18+
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

-------
v2:
 - move rq_status from struct request to struct blk_flush_queue
v3:
 - remove unnecessary '{}' pair.
v4:
 - let spinlock to protect 'fq->rq_status'
v5:
 - move rq_status after flush_running_idx member of struct blk_flush_queue
Signed-off-by: Jens Axboe <axboe@kernel.dk>
jackpot51 pushed a commit to pop-os/linux that referenced this pull request Oct 24, 2019
BugLink: https://bugs.launchpad.net/bugs/1848046

commit 8d69966 upstream.

We got a null pointer deference BUG_ON in blk_mq_rq_timed_out()
as following:

[  108.825472] BUG: kernel NULL pointer dereference, address: 0000000000000040
[  108.827059] PGD 0 P4D 0
[  108.827313] Oops: 0000 [#1] SMP PTI
[  108.827657] CPU: 6 PID: 198 Comm: kworker/6:1H Not tainted 5.3.0-rc8+ torvalds#431
[  108.829503] Workqueue: kblockd blk_mq_timeout_work
[  108.829913] RIP: 0010:blk_mq_check_expired+0x258/0x330
[  108.838191] Call Trace:
[  108.838406]  bt_iter+0x74/0x80
[  108.838665]  blk_mq_queue_tag_busy_iter+0x204/0x450
[  108.839074]  ? __switch_to_asm+0x34/0x70
[  108.839405]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.839823]  ? blk_mq_stop_hw_queue+0x40/0x40
[  108.840273]  ? syscall_return_via_sysret+0xf/0x7f
[  108.840732]  blk_mq_timeout_work+0x74/0x200
[  108.841151]  process_one_work+0x297/0x680
[  108.841550]  worker_thread+0x29c/0x6f0
[  108.841926]  ? rescuer_thread+0x580/0x580
[  108.842344]  kthread+0x16a/0x1a0
[  108.842666]  ? kthread_flush_work+0x170/0x170
[  108.843100]  ret_from_fork+0x35/0x40

The bug is caused by the race between timeout handle and completion for
flush request.

When timeout handle function blk_mq_rq_timed_out() try to read
'req->q->mq_ops', the 'req' have completed and reinitiated by next
flush request, which would call blk_rq_init() to clear 'req' as 0.

After commit 12f5b93 ("blk-mq: Remove generation seqeunce"),
normal requests lifetime are protected by refcount. Until 'rq->ref'
drop to zero, the request can really be free. Thus, these requests
cannot been reused before timeout handle finish.

However, flush request has defined .end_io and rq->end_io() is still
called even if 'rq->ref' doesn't drop to zero. After that, the 'flush_rq'
can be reused by the next flush request handle, resulting in null
pointer deference BUG ON.

We fix this problem by covering flush request with 'rq->ref'.
If the refcount is not zero, flush_end_io() return and wait the
last holder recall it. To record the request status, we add a new
entry 'rq_status', which will be used in flush_end_io().

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: stable@vger.kernel.org # v4.18+
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

-------
v2:
 - move rq_status from struct request to struct blk_flush_queue
v3:
 - remove unnecessary '{}' pair.
v4:
 - let spinlock to protect 'fq->rq_status'
v5:
 - move rq_status after flush_running_idx member of struct blk_flush_queue
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
tobetter pushed a commit to tobetter/linux that referenced this pull request Jan 18, 2023
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 12, 2025
When a page is freed it coalesces with a buddy into a higher
order page while possible. When the buddy page migrate type
differs, it is expected to be updated to match the one of the
page being freed.

However, only the first pageblock of the buddy page is updated,
while the rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths
(like below), since an inconsistency between migration type
of the list containing the page and the page-owned pageblocks
migration types is introduced.

The issue is first exposed with commit e0932b6 ("mm:
page_alloc: consolidate free page accounting"), where the
warnings were introduced, but it is observed in earlier
versions if similar warnings are added.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Fixes: e0932b6 ("mm: page_alloc: consolidate free page accounting")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 15, 2025
When a page is freed it coalesces with a buddy into a higher
order page while possible. When the buddy page migrate type
differs, it is expected to be updated to match the one of the
page being freed.

However, only the first pageblock of the buddy page is updated,
while the rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths
(like below), since an inconsistency between migration type
of the list containing the page and the page-owned pageblocks
migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Cc: stable@kernel.org
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 16, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 17, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 17, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
ajdlinux pushed a commit to ajdlinux/linux that referenced this pull request Dec 18, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 19, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 20, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 21, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 21, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 21, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 23, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Dec 23, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
bshephar pushed a commit to bshephar/linux that referenced this pull request Dec 30, 2025
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Jan 5, 2026
commit 7838a4e upstream.

When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Jan 6, 2026
commit 7838a4e upstream.

When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug torvalds#431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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