From f00bdce0455233a0b76dae6364442dca717a574c Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Tue, 23 Feb 2021 14:19:04 +0800 Subject: [PATCH 01/28] vdpa: set the virtqueue num during register This patch delay the queue number setting to vDPA device registering. This allows us to probe the virtqueue numbers between device allocation and registering. Reviewed-by: Stefano Garzarella Signed-off-by: Jason Wang Link: https://lore.kernel.org/r/20210223061905.422659-3-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin --- drivers/vdpa/ifcvf/ifcvf_main.c | 5 ++--- drivers/vdpa/mlx5/net/mlx5_vnet.c | 4 ++-- drivers/vdpa/vdpa.c | 18 ++++++++++-------- drivers/vdpa/vdpa_sim/vdpa_sim.c | 2 +- drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 2 +- include/linux/vdpa.h | 10 +++++----- 6 files changed, 21 insertions(+), 20 deletions(-) diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c index 7c8bbfcf6c3ebe..d555a6a5d1baf8 100644 --- a/drivers/vdpa/ifcvf/ifcvf_main.c +++ b/drivers/vdpa/ifcvf/ifcvf_main.c @@ -431,8 +431,7 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id) } adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa, - dev, &ifc_vdpa_ops, - IFCVF_MAX_QUEUE_PAIRS * 2, NULL); + dev, &ifc_vdpa_ops, NULL); if (adapter == NULL) { IFCVF_ERR(pdev, "Failed to allocate vDPA structure"); return -ENOMEM; @@ -456,7 +455,7 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id) for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) vf->vring[i].irq = -EINVAL; - ret = vdpa_register_device(&adapter->vdpa); + ret = vdpa_register_device(&adapter->vdpa, IFCVF_MAX_QUEUE_PAIRS * 2); if (ret) { IFCVF_ERR(pdev, "Failed to register ifcvf to vdpa bus"); goto err; diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c index 10e9b09932eb8a..71397fdafa6a4c 100644 --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c @@ -1982,7 +1982,7 @@ static int mlx5v_probe(struct auxiliary_device *adev, max_vqs = min_t(u32, max_vqs, MLX5_MAX_SUPPORTED_VQS); ndev = vdpa_alloc_device(struct mlx5_vdpa_net, mvdev.vdev, mdev->device, &mlx5_vdpa_ops, - 2 * mlx5_vdpa_max_qps(max_vqs), NULL); + NULL); if (IS_ERR(ndev)) return PTR_ERR(ndev); @@ -2009,7 +2009,7 @@ static int mlx5v_probe(struct auxiliary_device *adev, if (err) goto err_res; - err = vdpa_register_device(&mvdev->vdev); + err = vdpa_register_device(&mvdev->vdev, 2 * mlx5_vdpa_max_qps(max_vqs)); if (err) goto err_reg; diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c index da67f07e24fd48..5cffce67cab020 100644 --- a/drivers/vdpa/vdpa.c +++ b/drivers/vdpa/vdpa.c @@ -69,7 +69,6 @@ static void vdpa_release_dev(struct device *d) * initialized but before registered. * @parent: the parent device * @config: the bus operations that is supported by this device - * @nvqs: number of virtqueues supported by this device * @size: size of the parent structure that contains private data * @name: name of the vdpa device; optional. * @@ -81,7 +80,7 @@ static void vdpa_release_dev(struct device *d) */ struct vdpa_device *__vdpa_alloc_device(struct device *parent, const struct vdpa_config_ops *config, - int nvqs, size_t size, const char *name) + size_t size, const char *name) { struct vdpa_device *vdev; int err = -EINVAL; @@ -107,7 +106,6 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent, vdev->index = err; vdev->config = config; vdev->features_valid = false; - vdev->nvqs = nvqs; if (name) err = dev_set_name(&vdev->dev, "%s", name); @@ -136,10 +134,12 @@ static int vdpa_name_match(struct device *dev, const void *data) return (strcmp(dev_name(&vdev->dev), data) == 0); } -static int __vdpa_register_device(struct vdpa_device *vdev) +static int __vdpa_register_device(struct vdpa_device *vdev, int nvqs) { struct device *dev; + vdev->nvqs = nvqs; + lockdep_assert_held(&vdpa_dev_mutex); dev = bus_find_device(&vdpa_bus, NULL, dev_name(&vdev->dev), vdpa_name_match); if (dev) { @@ -155,15 +155,16 @@ static int __vdpa_register_device(struct vdpa_device *vdev) * Caller must invoke this routine in the management device dev_add() * callback after setting up valid mgmtdev for this vdpa device. * @vdev: the vdpa device to be registered to vDPA bus + * @nvqs: number of virtqueues supported by this device * * Returns an error when fail to add device to vDPA bus */ -int _vdpa_register_device(struct vdpa_device *vdev) +int _vdpa_register_device(struct vdpa_device *vdev, int nvqs) { if (!vdev->mdev) return -EINVAL; - return __vdpa_register_device(vdev); + return __vdpa_register_device(vdev, nvqs); } EXPORT_SYMBOL_GPL(_vdpa_register_device); @@ -171,15 +172,16 @@ EXPORT_SYMBOL_GPL(_vdpa_register_device); * vdpa_register_device - register a vDPA device * Callers must have a succeed call of vdpa_alloc_device() before. * @vdev: the vdpa device to be registered to vDPA bus + * @nvqs: number of virtqueues supported by this device * * Returns an error when fail to add to vDPA bus */ -int vdpa_register_device(struct vdpa_device *vdev) +int vdpa_register_device(struct vdpa_device *vdev, int nvqs) { int err; mutex_lock(&vdpa_dev_mutex); - err = __vdpa_register_device(vdev); + err = __vdpa_register_device(vdev, nvqs); mutex_unlock(&vdpa_dev_mutex); return err; } diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c index d5942842432d6b..5b6b2f87d40c65 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c @@ -235,7 +235,7 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr) ops = &vdpasim_config_ops; vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL, ops, - dev_attr->nvqs, dev_attr->name); + dev_attr->name); if (!vdpasim) goto err_alloc; diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c index d344c5b7c9149c..702be74877d27d 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c @@ -147,7 +147,7 @@ static int vdpasim_net_dev_add(struct vdpa_mgmt_dev *mdev, const char *name) if (IS_ERR(simdev)) return PTR_ERR(simdev); - ret = _vdpa_register_device(&simdev->vdpa); + ret = _vdpa_register_device(&simdev->vdpa, VDPASIM_NET_VQ_NUM); if (ret) goto reg_err; diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h index 4ab5494503a830..15fa085fab0573 100644 --- a/include/linux/vdpa.h +++ b/include/linux/vdpa.h @@ -250,20 +250,20 @@ struct vdpa_config_ops { struct vdpa_device *__vdpa_alloc_device(struct device *parent, const struct vdpa_config_ops *config, - int nvqs, size_t size, const char *name); + size_t size, const char *name); -#define vdpa_alloc_device(dev_struct, member, parent, config, nvqs, name) \ +#define vdpa_alloc_device(dev_struct, member, parent, config, name) \ container_of(__vdpa_alloc_device( \ - parent, config, nvqs, \ + parent, config, \ sizeof(dev_struct) + \ BUILD_BUG_ON_ZERO(offsetof( \ dev_struct, member)), name), \ dev_struct, member) -int vdpa_register_device(struct vdpa_device *vdev); +int vdpa_register_device(struct vdpa_device *vdev, int nvqs); void vdpa_unregister_device(struct vdpa_device *vdev); -int _vdpa_register_device(struct vdpa_device *vdev); +int _vdpa_register_device(struct vdpa_device *vdev, int nvqs); void _vdpa_unregister_device(struct vdpa_device *vdev); /** From 5808fecc572391867fcd929662b29c12e6d08d81 Mon Sep 17 00:00:00 2001 From: Ritesh Harjani Date: Tue, 9 Mar 2021 09:29:11 -0800 Subject: [PATCH 02/28] iomap: Fix negative assignment to unsigned sis->pages in iomap_swapfile_activate In case if isi.nr_pages is 0, we are making sis->pages (which is unsigned int) a huge value in iomap_swapfile_activate() by assigning -1. This could cause a kernel crash in kernel v4.18 (with below signature). Or could lead to unknown issues on latest kernel if the fake big swap gets used. Fix this issue by returning -EINVAL in case of nr_pages is 0, since it is anyway a invalid swapfile. Looks like this issue will be hit when we have pagesize < blocksize type of configuration. I was able to hit the issue in case of a tiny swap file with below test script. https://raw.githubusercontent.com/riteshharjani/LinuxStudy/master/scripts/swap-issue.sh kernel crash analysis on v4.18 ============================== On v4.18 kernel, it causes a kernel panic, since sis->pages becomes a huge value and isi.nr_extents is 0. When 0 is returned it is considered as a swapfile over NFS and SWP_FILE is set (sis->flags |= SWP_FILE). Then when swapoff was getting called it was calling a_ops->swap_deactivate() if (sis->flags & SWP_FILE) is true. Since a_ops->swap_deactivate() is NULL in case of XFS, it causes below panic. Panic signature on v4.18 kernel: ======================================= root@qemu:/home/qemu# [ 8291.723351] XFS (loop2): Unmounting Filesystem [ 8292.123104] XFS (loop2): Mounting V5 Filesystem [ 8292.132451] XFS (loop2): Ending clean mount [ 8292.263362] Adding 4294967232k swap on /mnt1/test/swapfile. Priority:-2 extents:1 across:274877906880k [ 8292.277834] Unable to handle kernel paging request for instruction fetch [ 8292.278677] Faulting instruction address: 0x00000000 cpu 0x19: Vector: 400 (Instruction Access) at [c0000009dd5b7ad0] pc: 0000000000000000 lr: c0000000003eb9dc: destroy_swap_extents+0xfc/0x120 sp: c0000009dd5b7d50 msr: 8000000040009033 current = 0xc0000009b6710080 paca = 0xc00000003ffcb280 irqmask: 0x03 irq_happened: 0x01 pid = 5604, comm = swapoff Linux version 4.18.0 (riteshh@xxxxxxx) (gcc version 8.4.0 (Ubuntu 8.4.0-1ubuntu1~18.04)) #57 SMP Wed Mar 3 01:33:04 CST 2021 enter ? for help [link register ] c0000000003eb9dc destroy_swap_extents+0xfc/0x120 [c0000009dd5b7d50] c0000000025a7058 proc_poll_event+0x0/0x4 (unreliable) [c0000009dd5b7da0] c0000000003f0498 sys_swapoff+0x3f8/0x910 [c0000009dd5b7e30] c00000000000bbe4 system_call+0x5c/0x70 Exception: c01 (System Call) at 00007ffff7d208d8 Signed-off-by: Ritesh Harjani [djwong: rework the comment to provide more details] Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig --- fs/iomap/swapfile.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/fs/iomap/swapfile.c b/fs/iomap/swapfile.c index a648dbf6991e4e..a5e478de141744 100644 --- a/fs/iomap/swapfile.c +++ b/fs/iomap/swapfile.c @@ -170,6 +170,16 @@ int iomap_swapfile_activate(struct swap_info_struct *sis, return ret; } + /* + * If this swapfile doesn't contain even a single page-aligned + * contiguous range of blocks, reject this useless swapfile to + * prevent confusion later on. + */ + if (isi.nr_pages == 0) { + pr_warn("swapon: Cannot find a single usable page in file.\n"); + return -EINVAL; + } + *pagespan = 1 + isi.highest_ppage - isi.lowest_ppage; sis->max = isi.nr_pages; sis->pages = isi.nr_pages - 1; From b5a08423da9da59c7f38ed8dbb6dd6cbbe9024a4 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Tue, 2 Mar 2021 09:32:52 -0800 Subject: [PATCH 03/28] xfs: fix quota accounting when a mount is idmapped Nowadays, we indirectly use the idmap-aware helper functions in the VFS to set the initial uid and gid of a file being created. Unfortunately, we didn't convert the quota code, which means we attach the wrong dquots to files created on an idmapped mount. Fixes: f736d93d76d3 ("xfs: support idmapped mounts") Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Acked-by: Christian Brauner Reviewed-by: Dave Chinner --- fs/xfs/xfs_inode.c | 14 ++++++++------ fs/xfs/xfs_symlink.c | 3 ++- 2 files changed, 10 insertions(+), 7 deletions(-) diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 46a861d55e487b..f93370bd7b1e38 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -1007,9 +1007,10 @@ xfs_create( /* * Make sure that we have allocated dquot(s) on disk. */ - error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid, - XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, - &udqp, &gdqp, &pdqp); + error = xfs_qm_vop_dqalloc(dp, fsuid_into_mnt(mnt_userns), + fsgid_into_mnt(mnt_userns), prid, + XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, + &udqp, &gdqp, &pdqp); if (error) return error; @@ -1157,9 +1158,10 @@ xfs_create_tmpfile( /* * Make sure that we have allocated dquot(s) on disk. */ - error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid, - XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, - &udqp, &gdqp, &pdqp); + error = xfs_qm_vop_dqalloc(dp, fsuid_into_mnt(mnt_userns), + fsgid_into_mnt(mnt_userns), prid, + XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, + &udqp, &gdqp, &pdqp); if (error) return error; diff --git a/fs/xfs/xfs_symlink.c b/fs/xfs/xfs_symlink.c index 1379013d74b887..7f368b10ded1bf 100644 --- a/fs/xfs/xfs_symlink.c +++ b/fs/xfs/xfs_symlink.c @@ -182,7 +182,8 @@ xfs_symlink( /* * Make sure that we have allocated dquot(s) on disk. */ - error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid, + error = xfs_qm_vop_dqalloc(dp, fsuid_into_mnt(mnt_userns), + fsgid_into_mnt(mnt_userns), prid, XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp, &pdqp); if (error) From da98b54d02981de5b07d8044b2a632bf6ba3ac45 Mon Sep 17 00:00:00 2001 From: Tang Bin Date: Mon, 22 Feb 2021 13:57:24 +0800 Subject: [PATCH 04/28] virtio-mmio: Use to_virtio_mmio_device() to simply code The file virtio_mmio.c has defined the function to_virtio_mmio_device, so use it instead of container_of() to simply code. Signed-off-by: Tang Bin Link: https://lore.kernel.org/r/20210222055724.220-1-tangbin@cmss.chinamobile.com Signed-off-by: Michael S. Tsirkin --- drivers/virtio/virtio_mmio.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index a286d22b6551cc..56128b9c46ebaa 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -548,8 +548,7 @@ static void virtio_mmio_release_dev(struct device *_d) { struct virtio_device *vdev = container_of(_d, struct virtio_device, dev); - struct virtio_mmio_device *vm_dev = - container_of(vdev, struct virtio_mmio_device, vdev); + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); struct platform_device *pdev = vm_dev->pdev; devm_kfree(&pdev->dev, vm_dev); From bc22ed2ea1121f9d9ba3f85c524cb857d54a2d00 Mon Sep 17 00:00:00 2001 From: Xianting Tian Date: Sat, 20 Feb 2021 11:28:18 -0500 Subject: [PATCH 05/28] virtio: remove export for virtio_config_{enable, disable} virtio_config_enable(), virtio_config_disable() are only used inside drivers/virtio/virtio.c, so it doesn't need export the symbols. Signed-off-by: Xianting Tian Link: https://lore.kernel.org/r/1613838498-8791-1-git-send-email-xianting_tian@126.com Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang Reviewed-by: Stefano Garzarella --- drivers/virtio/virtio.c | 6 ++---- include/linux/virtio.h | 2 -- 2 files changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index 42e09cc1b8ac5a..4b15c00c0a0afc 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -141,15 +141,14 @@ void virtio_config_changed(struct virtio_device *dev) } EXPORT_SYMBOL_GPL(virtio_config_changed); -void virtio_config_disable(struct virtio_device *dev) +static void virtio_config_disable(struct virtio_device *dev) { spin_lock_irq(&dev->config_lock); dev->config_enabled = false; spin_unlock_irq(&dev->config_lock); } -EXPORT_SYMBOL_GPL(virtio_config_disable); -void virtio_config_enable(struct virtio_device *dev) +static void virtio_config_enable(struct virtio_device *dev) { spin_lock_irq(&dev->config_lock); dev->config_enabled = true; @@ -158,7 +157,6 @@ void virtio_config_enable(struct virtio_device *dev) dev->config_change_pending = false; spin_unlock_irq(&dev->config_lock); } -EXPORT_SYMBOL_GPL(virtio_config_enable); void virtio_add_status(struct virtio_device *dev, unsigned int status) { diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 55ea329fe72a42..b1894e0323fae4 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -132,8 +132,6 @@ bool is_virtio_device(struct device *dev); void virtio_break_device(struct virtio_device *dev); void virtio_config_changed(struct virtio_device *dev); -void virtio_config_disable(struct virtio_device *dev); -void virtio_config_enable(struct virtio_device *dev); int virtio_finalize_features(struct virtio_device *dev); #ifdef CONFIG_PM_SLEEP int virtio_device_freeze(struct virtio_device *dev); From aa443ac20445ad79afc9aa589727e5d9ee88dc2f Mon Sep 17 00:00:00 2001 From: Parav Pandit Date: Sat, 13 Feb 2021 20:39:51 +0200 Subject: [PATCH 06/28] vdpa_sim: Skip typecasting from void* Typecasting from void* to virtio_net_config* is not needed. Remove it. Signed-off-by: Parav Pandit Link: https://lore.kernel.org/r/20210213183951.248324-1-parav@nvidia.com Signed-off-by: Michael S. Tsirkin --- drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c index 702be74877d27d..a1ab6163f7d13b 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c @@ -110,8 +110,7 @@ static void vdpasim_net_work(struct work_struct *work) static void vdpasim_net_get_config(struct vdpasim *vdpasim, void *config) { - struct virtio_net_config *net_config = - (struct virtio_net_config *)config; + struct virtio_net_config *net_config = config; net_config->mtu = cpu_to_vdpasim16(vdpasim, 1500); net_config->status = cpu_to_vdpasim16(vdpasim, VIRTIO_NET_S_LINK_UP); From 4c050286bb202cffd5467c1cba982dff391d62e1 Mon Sep 17 00:00:00 2001 From: Gautam Dawar Date: Wed, 24 Feb 2021 17:18:45 +0530 Subject: [PATCH 07/28] vhost_vdpa: fix the missing irq_bypass_unregister_producer() invocation When qemu with vhost-vdpa netdevice is run for the first time, it works well. But after the VM is powered off, the next qemu run causes kernel panic due to a NULL pointer dereference in irq_bypass_register_producer(). When the VM is powered off, vhost_vdpa_clean_irq() misses on calling irq_bypass_unregister_producer() for irq 0 because of the existing check. This leaves stale producer nodes, which are reset in vhost_vring_call_reset() when vhost_dev_init() is invoked during the second qemu run. As the node member of struct irq_bypass_producer is also initialized to zero, traversal on the producers list causes crash due to NULL pointer dereference. Fixes: 2cf1ba9a4d15c ("vhost_vdpa: implement IRQ offloading in vhost_vdpa") Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=211711 Signed-off-by: Gautam Dawar Acked-by: Jason Wang Link: https://lore.kernel.org/r/20210224114845.104173-1-gdawar.xilinx@gmail.com Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vdpa.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index ef688c8c0e0e6f..dfdd8e4a8b08e0 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -900,14 +900,10 @@ static int vhost_vdpa_open(struct inode *inode, struct file *filep) static void vhost_vdpa_clean_irq(struct vhost_vdpa *v) { - struct vhost_virtqueue *vq; int i; - for (i = 0; i < v->nvqs; i++) { - vq = &v->vqs[i]; - if (vq->call_ctx.producer.irq) - irq_bypass_unregister_producer(&vq->call_ctx.producer); - } + for (i = 0; i < v->nvqs; i++) + vhost_vdpa_unsetup_vq_irq(v, i); } static int vhost_vdpa_release(struct inode *inode, struct file *filep) From beb691e69f4dec7bfe8b81b509848acfd1f0dbf9 Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Fri, 12 Mar 2021 15:09:13 +0100 Subject: [PATCH 08/28] vhost: Fix vhost_vq_reset() vhost_reset_is_le() is vhost_init_is_le(), and in the case of cross-endian legacy, vhost_init_is_le() depends on vq->user_be. vq->user_be is set by vhost_disable_cross_endian(). But in vhost_vq_reset(), we have: vhost_reset_is_le(vq); vhost_disable_cross_endian(vq); And so user_be is used before being set. To fix that, reverse the lines order as there is no other dependency between them. Signed-off-by: Laurent Vivier Link: https://lore.kernel.org/r/20210312140913.788592-1-lvivier@redhat.com Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index a262e12c6dc26f..5ccb0705beae17 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -332,8 +332,8 @@ static void vhost_vq_reset(struct vhost_dev *dev, vq->error_ctx = NULL; vq->kick = NULL; vq->log_ctx = NULL; - vhost_reset_is_le(vq); vhost_disable_cross_endian(vq); + vhost_reset_is_le(vq); vq->busyloop_timeout = 0; vq->umem = NULL; vq->iotlb = NULL; From f6bbf0010ba004f5e90c7aefdebc0ee4bd3283b9 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Thu, 11 Mar 2021 14:52:56 +0100 Subject: [PATCH 09/28] vhost-vdpa: fix use-after-free of v->config_ctx When the 'v->config_ctx' eventfd_ctx reference is released we didn't set it to NULL. So if the same character device (e.g. /dev/vhost-vdpa-0) is re-opened, the 'v->config_ctx' is invalid and calling again vhost_vdpa_config_put() causes use-after-free issues like the following refcount_t underflow: refcount_t: underflow; use-after-free. WARNING: CPU: 2 PID: 872 at lib/refcount.c:28 refcount_warn_saturate+0xae/0xf0 RIP: 0010:refcount_warn_saturate+0xae/0xf0 Call Trace: eventfd_ctx_put+0x5b/0x70 vhost_vdpa_release+0xcd/0x150 [vhost_vdpa] __fput+0x8e/0x240 ____fput+0xe/0x10 task_work_run+0x66/0xa0 exit_to_user_mode_prepare+0x118/0x120 syscall_exit_to_user_mode+0x21/0x50 ? __x64_sys_close+0x12/0x40 do_syscall_64+0x45/0x50 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixes: 776f395004d8 ("vhost_vdpa: Support config interrupt in vdpa") Cc: lingshan.zhu@intel.com Cc: stable@vger.kernel.org Signed-off-by: Stefano Garzarella Link: https://lore.kernel.org/r/20210311135257.109460-2-sgarzare@redhat.com Signed-off-by: Michael S. Tsirkin Reviewed-by: Zhu Lingshan Acked-by: Jason Wang --- drivers/vhost/vdpa.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index dfdd8e4a8b08e0..4fc768813c4ad2 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -308,8 +308,10 @@ static long vhost_vdpa_get_vring_num(struct vhost_vdpa *v, u16 __user *argp) static void vhost_vdpa_config_put(struct vhost_vdpa *v) { - if (v->config_ctx) + if (v->config_ctx) { eventfd_ctx_put(v->config_ctx); + v->config_ctx = NULL; + } } static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 __user *argp) From 0bde59c1723a29e294765c96dbe5c7fb639c2f96 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Thu, 11 Mar 2021 14:52:57 +0100 Subject: [PATCH 10/28] vhost-vdpa: set v->config_ctx to NULL if eventfd_ctx_fdget() fails In vhost_vdpa_set_config_call() if eventfd_ctx_fdget() fails the 'v->config_ctx' contains an error instead of a valid pointer. Since we consider 'v->config_ctx' valid if it is not NULL, we should set it to NULL in this case to avoid to use an invalid pointer in other functions such as vhost_vdpa_config_put(). Fixes: 776f395004d8 ("vhost_vdpa: Support config interrupt in vdpa") Cc: lingshan.zhu@intel.com Cc: stable@vger.kernel.org Signed-off-by: Stefano Garzarella Link: https://lore.kernel.org/r/20210311135257.109460-3-sgarzare@redhat.com Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang --- drivers/vhost/vdpa.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index 4fc768813c4ad2..e0a27e33629356 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -331,8 +331,12 @@ static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 __user *argp) if (!IS_ERR_OR_NULL(ctx)) eventfd_ctx_put(ctx); - if (IS_ERR(v->config_ctx)) - return PTR_ERR(v->config_ctx); + if (IS_ERR(v->config_ctx)) { + long ret = PTR_ERR(v->config_ctx); + + v->config_ctx = NULL; + return ret; + } v->vdpa->config->set_config_cb(v->vdpa, &cb); From d336f7ebc65007f5831e2297e6f3383ae8dbf8ed Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Tue, 2 Mar 2021 09:32:53 -0800 Subject: [PATCH 11/28] xfs: force log and push AIL to clear pinned inodes when aborting mount If we allocate quota inodes in the process of mounting a filesystem but then decide to abort the mount, it's possible that the quota inodes are sitting around pinned by the log. Now that inode reclaim relies on the AIL to flush inodes, we have to force the log and push the AIL in between releasing the quota inodes and kicking off reclaim to tear down all the incore inodes. Do this by extracting the bits we need from the unmount path and reusing them. As an added bonus, failed writes during a failed mount will not retry forever now. This was originally found during a fuzz test of metadata directories (xfs/1546), but the actual symptom was that reclaim hung up on the quota inodes. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Reviewed-by: Dave Chinner --- fs/xfs/xfs_mount.c | 90 +++++++++++++++++++++++----------------------- 1 file changed, 44 insertions(+), 46 deletions(-) diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index 52370d0a3f4343..1c97b155a8ee71 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -634,6 +634,47 @@ xfs_check_summary_counts( return xfs_initialize_perag_data(mp, mp->m_sb.sb_agcount); } +/* + * Flush and reclaim dirty inodes in preparation for unmount. Inodes and + * internal inode structures can be sitting in the CIL and AIL at this point, + * so we need to unpin them, write them back and/or reclaim them before unmount + * can proceed. + * + * An inode cluster that has been freed can have its buffer still pinned in + * memory because the transaction is still sitting in a iclog. The stale inodes + * on that buffer will be pinned to the buffer until the transaction hits the + * disk and the callbacks run. Pushing the AIL will skip the stale inodes and + * may never see the pinned buffer, so nothing will push out the iclog and + * unpin the buffer. + * + * Hence we need to force the log to unpin everything first. However, log + * forces don't wait for the discards they issue to complete, so we have to + * explicitly wait for them to complete here as well. + * + * Then we can tell the world we are unmounting so that error handling knows + * that the filesystem is going away and we should error out anything that we + * have been retrying in the background. This will prevent never-ending + * retries in AIL pushing from hanging the unmount. + * + * Finally, we can push the AIL to clean all the remaining dirty objects, then + * reclaim the remaining inodes that are still in memory at this point in time. + */ +static void +xfs_unmount_flush_inodes( + struct xfs_mount *mp) +{ + xfs_log_force(mp, XFS_LOG_SYNC); + xfs_extent_busy_wait_all(mp); + flush_workqueue(xfs_discard_wq); + + mp->m_flags |= XFS_MOUNT_UNMOUNTING; + + xfs_ail_push_all_sync(mp->m_ail); + cancel_delayed_work_sync(&mp->m_reclaim_work); + xfs_reclaim_inodes(mp); + xfs_health_unmount(mp); +} + /* * This function does the following on an initial mount of a file system: * - reads the superblock from disk and init the mount struct @@ -1008,7 +1049,7 @@ xfs_mountfs( /* Clean out dquots that might be in memory after quotacheck. */ xfs_qm_unmount(mp); /* - * Cancel all delayed reclaim work and reclaim the inodes directly. + * Flush all inode reclamation work and flush the log. * We have to do this /after/ rtunmount and qm_unmount because those * two will have scheduled delayed reclaim for the rt/quota inodes. * @@ -1018,11 +1059,8 @@ xfs_mountfs( * qm_unmount_quotas and therefore rely on qm_unmount to release the * quota inodes. */ - cancel_delayed_work_sync(&mp->m_reclaim_work); - xfs_reclaim_inodes(mp); - xfs_health_unmount(mp); + xfs_unmount_flush_inodes(mp); out_log_dealloc: - mp->m_flags |= XFS_MOUNT_UNMOUNTING; xfs_log_mount_cancel(mp); out_fail_wait: if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) @@ -1063,47 +1101,7 @@ xfs_unmountfs( xfs_rtunmount_inodes(mp); xfs_irele(mp->m_rootip); - /* - * We can potentially deadlock here if we have an inode cluster - * that has been freed has its buffer still pinned in memory because - * the transaction is still sitting in a iclog. The stale inodes - * on that buffer will be pinned to the buffer until the - * transaction hits the disk and the callbacks run. Pushing the AIL will - * skip the stale inodes and may never see the pinned buffer, so - * nothing will push out the iclog and unpin the buffer. Hence we - * need to force the log here to ensure all items are flushed into the - * AIL before we go any further. - */ - xfs_log_force(mp, XFS_LOG_SYNC); - - /* - * Wait for all busy extents to be freed, including completion of - * any discard operation. - */ - xfs_extent_busy_wait_all(mp); - flush_workqueue(xfs_discard_wq); - - /* - * We now need to tell the world we are unmounting. This will allow - * us to detect that the filesystem is going away and we should error - * out anything that we have been retrying in the background. This will - * prevent neverending retries in AIL pushing from hanging the unmount. - */ - mp->m_flags |= XFS_MOUNT_UNMOUNTING; - - /* - * Flush all pending changes from the AIL. - */ - xfs_ail_push_all_sync(mp->m_ail); - - /* - * Reclaim all inodes. At this point there should be no dirty inodes and - * none should be pinned or locked. Stop background inode reclaim here - * if it is still running. - */ - cancel_delayed_work_sync(&mp->m_reclaim_work); - xfs_reclaim_inodes(mp); - xfs_health_unmount(mp); + xfs_unmount_flush_inodes(mp); xfs_qm_unmount(mp); From 08a204387e8063ba7375481281701137bd553dee Mon Sep 17 00:00:00 2001 From: Bhaskar Chowdhury Date: Tue, 9 Mar 2021 09:45:51 -0800 Subject: [PATCH 12/28] docs: ABI: Fix the spelling oustanding to outstanding in the file sysfs-fs-xfs s/oustanding/outstanding/ Signed-off-by: Bhaskar Chowdhury Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- Documentation/ABI/testing/sysfs-fs-xfs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/sysfs-fs-xfs b/Documentation/ABI/testing/sysfs-fs-xfs index ea0cc8c42093fd..f704925f6fe93b 100644 --- a/Documentation/ABI/testing/sysfs-fs-xfs +++ b/Documentation/ABI/testing/sysfs-fs-xfs @@ -33,7 +33,7 @@ Contact: xfs@oss.sgi.com Description: The current state of the log write grant head. It represents the total log reservation of all currently - oustanding transactions, including regrants due to + outstanding transactions, including regrants due to rolling transactions. The grant head is exported in "cycle:bytes" format. Users: xfstests From 8723d5ba8bdae1c41be7a6fc8469dc9aa551e7d0 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sun, 14 Mar 2021 10:59:39 -0700 Subject: [PATCH 13/28] xfs: also reject BULKSTAT_SINGLE in a mount user namespace BULKSTAT_SINGLE exposed the ondisk uids/gids just like bulkstat, and can be called on any inode, including ones not visible in the current mount. Fixes: f736d93d76d3 ("xfs: support idmapped mounts") Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_itable.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c index ca310a125d1e14..3498b97fb06d31 100644 --- a/fs/xfs/xfs_itable.c +++ b/fs/xfs/xfs_itable.c @@ -168,6 +168,12 @@ xfs_bulkstat_one( }; int error; + if (breq->mnt_userns != &init_user_ns) { + xfs_warn_ratelimited(breq->mp, + "bulkstat not supported inside of idmapped mounts."); + return -EINVAL; + } + ASSERT(breq->icount == 1); bc.buf = kmem_zalloc(sizeof(struct xfs_bulkstat), From d2dcc8ed8ec650a793e81d8b2222146eb6ddd84f Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Mon, 8 Mar 2021 17:20:17 +0800 Subject: [PATCH 14/28] btrfs: fix wrong offset to zero out range beyond i_size [BUG] The test generic/091 fails , with the following output: fsx -N 10000 -o 128000 -l 500000 -r PSIZE -t BSIZE -w BSIZE -Z -W mapped writes DISABLED Seed set to 1 main: filesystem does not support fallocate mode FALLOC_FL_COLLAPSE_RANGE, disabling! main: filesystem does not support fallocate mode FALLOC_FL_INSERT_RANGE, disabling! skipping zero size read truncating to largest ever: 0xe400 copying to largest ever: 0x1f400 cloning to largest ever: 0x70000 cloning to largest ever: 0x77000 fallocating to largest ever: 0x7a120 Mapped Read: non-zero data past EOF (0x3a7ff) page offset 0x800 is 0xf2e1 <<< ... [CAUSE] In commit c28ea613fafa ("btrfs: subpage: fix the false data csum mismatch error") end_bio_extent_readpage() changes to only zero the range inside the bvec for incoming subpage support. But that commit is using incorrect offset to calculate the start. For subpage, we can have a case that the whole bvec is beyond isize, thus we need to calculate the correct offset. But the offending commit is using @end (bvec end), other than @start (bvec start) to calculate the start offset. This means, we only zero the last byte of the bvec, not from the isize. This stupid bug makes the range beyond isize is not properly zeroed, and failed above test. [FIX] Use correct @start to calculate the range start. Reported-by: kernel test robot Fixes: c28ea613fafa ("btrfs: subpage: fix the false data csum mismatch error") Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- fs/btrfs/extent_io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 4671c99d468ddd..f3d7be975c3a54 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -3020,7 +3020,7 @@ static void end_bio_extent_readpage(struct bio *bio) */ if (page->index == end_index && i_size <= end) { u32 zero_start = max(offset_in_page(i_size), - offset_in_page(end)); + offset_in_page(start)); zero_user_segment(page, zero_start, offset_in_page(end) + 1); From fbf48bb0b197e6894a04c714728c952af7153bf3 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Wed, 3 Mar 2021 18:41:51 +0800 Subject: [PATCH 15/28] btrfs: track qgroup released data in own variable in insert_prealloc_file_extent There is a piece of weird code in insert_prealloc_file_extent(), which looks like: ret = btrfs_qgroup_release_data(inode, file_offset, len); if (ret < 0) return ERR_PTR(ret); if (trans) { ret = insert_reserved_file_extent(trans, inode, file_offset, &stack_fi, true, ret); ... } extent_info.is_new_extent = true; extent_info.qgroup_reserved = ret; ... Note how the variable @ret is abused here, and if anyone is adding code just after btrfs_qgroup_release_data() call, it's super easy to overwrite the @ret and cause tons of qgroup related bugs. Fix such abuse by introducing new variable @qgroup_released, so that we won't reuse the existing variable @ret. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/inode.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index c35b724a56116d..77182be403c56b 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -9873,6 +9873,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent( struct btrfs_path *path; u64 start = ins->objectid; u64 len = ins->offset; + int qgroup_released; int ret; memset(&stack_fi, 0, sizeof(stack_fi)); @@ -9885,14 +9886,14 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent( btrfs_set_stack_file_extent_compression(&stack_fi, BTRFS_COMPRESS_NONE); /* Encryption and other encoding is reserved and all 0 */ - ret = btrfs_qgroup_release_data(inode, file_offset, len); - if (ret < 0) - return ERR_PTR(ret); + qgroup_released = btrfs_qgroup_release_data(inode, file_offset, len); + if (qgroup_released < 0) + return ERR_PTR(qgroup_released); if (trans) { ret = insert_reserved_file_extent(trans, inode, file_offset, &stack_fi, - true, ret); + true, qgroup_released); if (ret) return ERR_PTR(ret); return trans; @@ -9905,7 +9906,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent( extent_info.file_offset = file_offset; extent_info.extent_buf = (char *)&stack_fi; extent_info.is_new_extent = true; - extent_info.qgroup_reserved = ret; + extent_info.qgroup_reserved = qgroup_released; extent_info.insertions = 0; path = btrfs_alloc_path(); From a3ee79bd8fe17812d2305ccc4bf81bfeab395576 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Wed, 3 Mar 2021 18:41:52 +0800 Subject: [PATCH 16/28] btrfs: fix qgroup data rsv leak caused by falloc failure [BUG] When running fsstress with only falloc workload, and a very low qgroup limit set, we can get qgroup data rsv leak at unmount time. BTRFS warning (device dm-0): qgroup 0/5 has unreleased space, type 0 rsv 20480 BTRFS error (device dm-0): qgroup reserved space leaked The minimal reproducer looks like: #!/bin/bash dev=/dev/test/test mnt="/mnt/btrfs" fsstress=~/xfstests-dev/ltp/fsstress runtime=8 workload() { umount $dev &> /dev/null umount $mnt &> /dev/null mkfs.btrfs -f $dev > /dev/null mount $dev $mnt btrfs quota en $mnt btrfs quota rescan -w $mnt btrfs qgroup limit 16m 0/5 $mnt $fsstress -w -z -f creat=10 -f fallocate=10 -p 2 -n 100 \ -d $mnt -v > /tmp/fsstress umount $mnt if dmesg | grep leak ; then echo "!!! FAILED !!!" exit 1 fi } for (( i=0; i < $runtime; i++)); do echo "=== $i/$runtime===" workload done Normally it would fail before round 4. [CAUSE] In function insert_prealloc_file_extent(), we first call btrfs_qgroup_release_data() to know how many bytes are reserved for qgroup data rsv. Then use that @qgroup_released number to continue our work. But after we call btrfs_qgroup_release_data(), we should either queue @qgroup_released to delayed ref or free them manually in error path. Unfortunately, we lack the error handling to free the released bytes, leaking qgroup data rsv. All the error handling function outside won't help at all, as we have released the range, meaning in inode io tree, the EXTENT_QGROUP_RESERVED bit is already cleared, thus all btrfs_qgroup_free_data() call won't free any data rsv. [FIX] Add free_qgroup tag to manually free the released qgroup data rsv. Reported-by: Nikolay Borisov Reported-by: David Sterba Fixes: 9729f10a608f ("btrfs: inode: move qgroup reserved space release to the callers of insert_reserved_file_extent()") CC: stable@vger.kernel.org # 5.10+ Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- fs/btrfs/inode.c | 24 +++++++++++++++++++----- 1 file changed, 19 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 77182be403c56b..ea5ede619220cb 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -9895,7 +9895,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent( file_offset, &stack_fi, true, qgroup_released); if (ret) - return ERR_PTR(ret); + goto free_qgroup; return trans; } @@ -9910,17 +9910,31 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent( extent_info.insertions = 0; path = btrfs_alloc_path(); - if (!path) - return ERR_PTR(-ENOMEM); + if (!path) { + ret = -ENOMEM; + goto free_qgroup; + } ret = btrfs_replace_file_extents(&inode->vfs_inode, path, file_offset, file_offset + len - 1, &extent_info, &trans); btrfs_free_path(path); if (ret) - return ERR_PTR(ret); - + goto free_qgroup; return trans; + +free_qgroup: + /* + * We have released qgroup data range at the beginning of the function, + * and normally qgroup_released bytes will be freed when committing + * transaction. + * But if we error out early, we have to free what we have released + * or we leak qgroup data reservation. + */ + btrfs_qgroup_free_refroot(inode->root->fs_info, + inode->root->root_key.objectid, qgroup_released, + BTRFS_QGROUP_RSV_DATA); + return ERR_PTR(ret); } static int __btrfs_prealloc_file_range(struct inode *inode, int mode, From e3d3b4157610164b0ec43d968b0dfedfe7c68992 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Thu, 11 Mar 2021 15:13:30 +0000 Subject: [PATCH 17/28] btrfs: zoned: fix linked list corruption after log root tree allocation failure When using a zoned filesystem, while syncing the log, if we fail to allocate the root node for the log root tree, we are not removing the log context we allocated on stack from the list of log contexts of the log root tree. This means after the return from btrfs_sync_log() we get a corrupted linked list. Fix this by allocating the node before adding our stack allocated context to the list of log contexts of the log root tree. Fixes: 3ddebf27fcd3a9 ("btrfs: zoned: reorder log node allocation on zoned filesystem") Reviewed-by: Johannes Thumshirn Reviewed-by: Naohiro Aota Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/tree-log.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 2f1acc9aea9ea0..92a3686277918a 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -3169,10 +3169,6 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, mutex_lock(&log_root_tree->log_mutex); - index2 = log_root_tree->log_transid % 2; - list_add_tail(&root_log_ctx.list, &log_root_tree->log_ctxs[index2]); - root_log_ctx.log_transid = log_root_tree->log_transid; - if (btrfs_is_zoned(fs_info)) { if (!log_root_tree->node) { ret = btrfs_alloc_log_tree_node(trans, log_root_tree); @@ -3183,6 +3179,10 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, } } + index2 = log_root_tree->log_transid % 2; + list_add_tail(&root_log_ctx.list, &log_root_tree->log_ctxs[index2]); + root_log_ctx.log_transid = log_root_tree->log_transid; + /* * Now we are safe to update the log_root_tree because we're under the * log_mutex, and we're a current writer so we're holding the commit From d9bb77d51e668a1a6d4530c1ea471574d0ce465f Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Mon, 15 Mar 2021 13:39:14 +0800 Subject: [PATCH 18/28] btrfs: subpage: fix wild pointer access during metadata read failure [BUG] When running fstests for btrfs subpage read-write test, it has a very high chance to crash at generic/475 with the following stack: BTRFS warning (device dm-8): direct IO failed ino 510 rw 1,34817 sector 0xcdf0 len 94208 err no 10 Unable to handle kernel paging request at virtual address ffff80001157e7c0 CPU: 2 PID: 687125 Comm: kworker/u12:4 Tainted: G WC 5.12.0-rc2-custom+ #5 Hardware name: Khadas VIM3 (DT) Workqueue: btrfs-endio-meta btrfs_work_helper [btrfs] pc : queued_spin_lock_slowpath+0x1a0/0x390 lr : do_raw_spin_lock+0xc4/0x11c Call trace: queued_spin_lock_slowpath+0x1a0/0x390 _raw_spin_lock+0x68/0x84 btree_readahead_hook+0x38/0xc0 [btrfs] end_bio_extent_readpage+0x504/0x5f4 [btrfs] bio_endio+0x170/0x1a4 end_workqueue_fn+0x3c/0x60 [btrfs] btrfs_work_helper+0x1b0/0x1b4 [btrfs] process_one_work+0x22c/0x430 worker_thread+0x70/0x3a0 kthread+0x13c/0x140 ret_from_fork+0x10/0x30 Code: 910020e0 8b0200c2 f861d884 aa0203e1 (f8246827) [CAUSE] In end_bio_extent_readpage(), if we hit an error during read, we will handle the error differently for data and metadata. For data we queue a repair, while for metadata, we record the error and let the caller choose what to do. But the code is still using page->private to grab extent buffer, which no longer points to extent buffer for subpage metadata pages. Thus this wild pointer access leads to above crash. [FIX] Introduce a helper, find_extent_buffer_readpage(), to grab extent buffer. The difference against find_extent_buffer_nospinlock() is: - Also handles regular sectorsize == PAGE_SIZE case - No extent buffer refs increase/decrease As extent buffer under IO must have non-zero refs, so this is safe Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/extent_io.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index f3d7be975c3a54..0d00a9cd123a87 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2885,6 +2885,35 @@ static void end_page_read(struct page *page, bool uptodate, u64 start, u32 len) btrfs_subpage_end_reader(fs_info, page, start, len); } +/* + * Find extent buffer for a givne bytenr. + * + * This is for end_bio_extent_readpage(), thus we can't do any unsafe locking + * in endio context. + */ +static struct extent_buffer *find_extent_buffer_readpage( + struct btrfs_fs_info *fs_info, struct page *page, u64 bytenr) +{ + struct extent_buffer *eb; + + /* + * For regular sectorsize, we can use page->private to grab extent + * buffer + */ + if (fs_info->sectorsize == PAGE_SIZE) { + ASSERT(PagePrivate(page) && page->private); + return (struct extent_buffer *)page->private; + } + + /* For subpage case, we need to lookup buffer radix tree */ + rcu_read_lock(); + eb = radix_tree_lookup(&fs_info->buffer_radix, + bytenr >> fs_info->sectorsize_bits); + rcu_read_unlock(); + ASSERT(eb); + return eb; +} + /* * after a readpage IO is done, we need to: * clear the uptodate bits on error @@ -2996,7 +3025,7 @@ static void end_bio_extent_readpage(struct bio *bio) } else { struct extent_buffer *eb; - eb = (struct extent_buffer *)page->private; + eb = find_extent_buffer_readpage(fs_info, page, start); set_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags); eb->read_mirror = mirror; atomic_dec(&eb->io_pages); From 60484cd9d50117017cf53d5310c6cd629600dc69 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Mon, 15 Mar 2021 13:39:15 +0800 Subject: [PATCH 19/28] btrfs: subpage: make readahead work properly In readahead infrastructure, we are using a lot of hard coded PAGE_SHIFT while we're not doing anything specific to PAGE_SIZE. One of the most affected part is the radix tree operation of btrfs_fs_info::reada_tree. If using PAGE_SHIFT, subpage metadata readahead is broken and does no help reading metadata ahead. Fix the problem by using btrfs_fs_info::sectorsize_bits so that readahead could work for subpage. Reviewed-by: Johannes Thumshirn Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/reada.c | 35 ++++++++++++++++++----------------- 1 file changed, 18 insertions(+), 17 deletions(-) diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c index 20fd4aa48a8ce0..06713a8fe26b4a 100644 --- a/fs/btrfs/reada.c +++ b/fs/btrfs/reada.c @@ -209,7 +209,7 @@ int btree_readahead_hook(struct extent_buffer *eb, int err) /* find extent */ spin_lock(&fs_info->reada_lock); re = radix_tree_lookup(&fs_info->reada_tree, - eb->start >> PAGE_SHIFT); + eb->start >> fs_info->sectorsize_bits); if (re) re->refcnt++; spin_unlock(&fs_info->reada_lock); @@ -240,7 +240,7 @@ static struct reada_zone *reada_find_zone(struct btrfs_device *dev, u64 logical, zone = NULL; spin_lock(&fs_info->reada_lock); ret = radix_tree_gang_lookup(&dev->reada_zones, (void **)&zone, - logical >> PAGE_SHIFT, 1); + logical >> fs_info->sectorsize_bits, 1); if (ret == 1 && logical >= zone->start && logical <= zone->end) { kref_get(&zone->refcnt); spin_unlock(&fs_info->reada_lock); @@ -283,13 +283,13 @@ static struct reada_zone *reada_find_zone(struct btrfs_device *dev, u64 logical, spin_lock(&fs_info->reada_lock); ret = radix_tree_insert(&dev->reada_zones, - (unsigned long)(zone->end >> PAGE_SHIFT), - zone); + (unsigned long)(zone->end >> fs_info->sectorsize_bits), + zone); if (ret == -EEXIST) { kfree(zone); ret = radix_tree_gang_lookup(&dev->reada_zones, (void **)&zone, - logical >> PAGE_SHIFT, 1); + logical >> fs_info->sectorsize_bits, 1); if (ret == 1 && logical >= zone->start && logical <= zone->end) kref_get(&zone->refcnt); else @@ -315,7 +315,7 @@ static struct reada_extent *reada_find_extent(struct btrfs_fs_info *fs_info, u64 length; int real_stripes; int nzones = 0; - unsigned long index = logical >> PAGE_SHIFT; + unsigned long index = logical >> fs_info->sectorsize_bits; int dev_replace_is_ongoing; int have_zone = 0; @@ -497,7 +497,7 @@ static void reada_extent_put(struct btrfs_fs_info *fs_info, struct reada_extent *re) { int i; - unsigned long index = re->logical >> PAGE_SHIFT; + unsigned long index = re->logical >> fs_info->sectorsize_bits; spin_lock(&fs_info->reada_lock); if (--re->refcnt) { @@ -538,11 +538,12 @@ static void reada_extent_put(struct btrfs_fs_info *fs_info, static void reada_zone_release(struct kref *kref) { struct reada_zone *zone = container_of(kref, struct reada_zone, refcnt); + struct btrfs_fs_info *fs_info = zone->device->fs_info; - lockdep_assert_held(&zone->device->fs_info->reada_lock); + lockdep_assert_held(&fs_info->reada_lock); radix_tree_delete(&zone->device->reada_zones, - zone->end >> PAGE_SHIFT); + zone->end >> fs_info->sectorsize_bits); kfree(zone); } @@ -593,7 +594,7 @@ static int reada_add_block(struct reada_control *rc, u64 logical, static void reada_peer_zones_set_lock(struct reada_zone *zone, int lock) { int i; - unsigned long index = zone->end >> PAGE_SHIFT; + unsigned long index = zone->end >> zone->device->fs_info->sectorsize_bits; for (i = 0; i < zone->ndevs; ++i) { struct reada_zone *peer; @@ -628,7 +629,7 @@ static int reada_pick_zone(struct btrfs_device *dev) (void **)&zone, index, 1); if (ret == 0) break; - index = (zone->end >> PAGE_SHIFT) + 1; + index = (zone->end >> dev->fs_info->sectorsize_bits) + 1; if (zone->locked) { if (zone->elems > top_locked_elems) { top_locked_elems = zone->elems; @@ -709,7 +710,7 @@ static int reada_start_machine_dev(struct btrfs_device *dev) * plugging to speed things up */ ret = radix_tree_gang_lookup(&dev->reada_extents, (void **)&re, - dev->reada_next >> PAGE_SHIFT, 1); + dev->reada_next >> fs_info->sectorsize_bits, 1); if (ret == 0 || re->logical > dev->reada_curr_zone->end) { ret = reada_pick_zone(dev); if (!ret) { @@ -718,7 +719,7 @@ static int reada_start_machine_dev(struct btrfs_device *dev) } re = NULL; ret = radix_tree_gang_lookup(&dev->reada_extents, (void **)&re, - dev->reada_next >> PAGE_SHIFT, 1); + dev->reada_next >> fs_info->sectorsize_bits, 1); } if (ret == 0) { spin_unlock(&fs_info->reada_lock); @@ -885,7 +886,7 @@ static void dump_devs(struct btrfs_fs_info *fs_info, int all) pr_cont(" curr off %llu", device->reada_next - zone->start); pr_cont("\n"); - index = (zone->end >> PAGE_SHIFT) + 1; + index = (zone->end >> fs_info->sectorsize_bits) + 1; } cnt = 0; index = 0; @@ -910,7 +911,7 @@ static void dump_devs(struct btrfs_fs_info *fs_info, int all) } } pr_cont("\n"); - index = (re->logical >> PAGE_SHIFT) + 1; + index = (re->logical >> fs_info->sectorsize_bits) + 1; if (++cnt > 15) break; } @@ -926,7 +927,7 @@ static void dump_devs(struct btrfs_fs_info *fs_info, int all) if (ret == 0) break; if (!re->scheduled) { - index = (re->logical >> PAGE_SHIFT) + 1; + index = (re->logical >> fs_info->sectorsize_bits) + 1; continue; } pr_debug("re: logical %llu size %u list empty %d scheduled %d", @@ -942,7 +943,7 @@ static void dump_devs(struct btrfs_fs_info *fs_info, int all) } } pr_cont("\n"); - index = (re->logical >> PAGE_SHIFT) + 1; + index = (re->logical >> fs_info->sectorsize_bits) + 1; } spin_unlock(&fs_info->reada_lock); } From 7dc4b2fdb27242faf40fc20ef83372b7033af050 Mon Sep 17 00:00:00 2001 From: Steve Sistare Date: Thu, 25 Feb 2021 11:25:02 -0800 Subject: [PATCH 20/28] vfio/type1: fix unmap all on ILP32 Some ILP32 architectures support mapping a 32-bit vaddr within a 64-bit iova space. The unmap-all code uses 32-bit SIZE_MAX as an upper bound on the extent of the mappings within iova space, so mappings above 4G cannot be found and unmapped. Use U64_MAX instead, and use u64 for size variables. This also fixes a static analysis bug found by the kernel test robot running smatch for ILP32. Fixes: 0f53afa12bae ("vfio/type1: unmap cleanup") Fixes: c19650995374 ("vfio/type1: implement unmap all") Reported-by: kernel test robot Reported-by: Dan Carpenter Signed-off-by: Steve Sistare Message-Id: <1614281102-230747-1-git-send-email-steven.sistare@oracle.com> Link: https://lore.kernel.org/linux-mm/20210222141043.GW2222@kadam Reviewed-by: Cornelia Huck Signed-off-by: Alex Williamson --- drivers/vfio/vfio_iommu_type1.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 4bb162c1d649b3..12d9905b429fd5 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -189,7 +189,7 @@ static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu, } static struct rb_node *vfio_find_dma_first_node(struct vfio_iommu *iommu, - dma_addr_t start, size_t size) + dma_addr_t start, u64 size) { struct rb_node *res = NULL; struct rb_node *node = iommu->dma_list.rb_node; @@ -1288,7 +1288,7 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, int ret = -EINVAL, retries = 0; unsigned long pgshift; dma_addr_t iova = unmap->iova; - unsigned long size = unmap->size; + u64 size = unmap->size; bool unmap_all = unmap->flags & VFIO_DMA_UNMAP_FLAG_ALL; bool invalidate_vaddr = unmap->flags & VFIO_DMA_UNMAP_FLAG_VADDR; struct rb_node *n, *first_n; @@ -1304,14 +1304,12 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, if (unmap_all) { if (iova || size) goto unlock; - size = SIZE_MAX; - } else if (!size || size & (pgsize - 1)) { + size = U64_MAX; + } else if (!size || size & (pgsize - 1) || + iova + size - 1 < iova || size > SIZE_MAX) { goto unlock; } - if (iova + size - 1 < iova || size > SIZE_MAX) - goto unlock; - /* When dirty tracking is enabled, allow only min supported pgsize */ if ((unmap->flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) && (!iommu->dirty_page_tracking || (bitmap->pgsize != pgsize))) { From 179209fa12709a3df8888c323b37315da2683c24 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Tue, 23 Feb 2021 15:17:46 -0400 Subject: [PATCH 21/28] vfio: IOMMU_API should be selected As IOMMU_API is a kconfig without a description (eg does not show in the menu) the correct operator is select not 'depends on'. Using 'depends on' for this kind of symbol means VFIO is not selectable unless some other random kconfig has already enabled IOMMU_API for it. Fixes: cba3345cc494 ("vfio: VFIO core") Signed-off-by: Jason Gunthorpe Message-Id: <1-v1-df057e0f92c3+91-vfio_arm_compile_test_jgg@nvidia.com> Reviewed-by: Eric Auger Signed-off-by: Alex Williamson --- drivers/vfio/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig index 5533df91b257d6..90c0525b1e0cf4 100644 --- a/drivers/vfio/Kconfig +++ b/drivers/vfio/Kconfig @@ -21,7 +21,7 @@ config VFIO_VIRQFD menuconfig VFIO tristate "VFIO Non-Privileged userspace driver framework" - depends on IOMMU_API + select IOMMU_API select VFIO_IOMMU_TYPE1 if (X86 || S390 || ARM || ARM64) help VFIO provides a framework for secure userspace device drivers. From d3d72a6dfffd3fcaac969786118162b596227f70 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Tue, 23 Feb 2021 15:17:47 -0400 Subject: [PATCH 22/28] vfio-platform: Add COMPILE_TEST to VFIO_PLATFORM x86 can build platform bus code too, so vfio-platform and all the platform reset implementations compile successfully on x86. Signed-off-by: Jason Gunthorpe Message-Id: <2-v1-df057e0f92c3+91-vfio_arm_compile_test_jgg@nvidia.com> Signed-off-by: Alex Williamson --- drivers/vfio/platform/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/vfio/platform/Kconfig b/drivers/vfio/platform/Kconfig index dc1a3c44f2c62b..233efde219cc10 100644 --- a/drivers/vfio/platform/Kconfig +++ b/drivers/vfio/platform/Kconfig @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only config VFIO_PLATFORM tristate "VFIO support for platform devices" - depends on VFIO && EVENTFD && (ARM || ARM64) + depends on VFIO && EVENTFD && (ARM || ARM64 || COMPILE_TEST) select VFIO_VIRQFD help Support for platform devices with VFIO. This is required to make From 3b49dfb08c750d4745ad42ec042288aba932b9d5 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Tue, 23 Feb 2021 15:17:48 -0400 Subject: [PATCH 23/28] ARM: amba: Allow some ARM_AMBA users to compile with COMPILE_TEST CONFIG_VFIO_AMBA has a light use of AMBA, adding some inline fallbacks when AMBA is disabled will allow it to be compiled under COMPILE_TEST and make VFIO easier to maintain. Signed-off-by: Jason Gunthorpe Message-Id: <3-v1-df057e0f92c3+91-vfio_arm_compile_test_jgg@nvidia.com> Reviewed-by: Eric Auger Signed-off-by: Alex Williamson --- drivers/vfio/platform/Kconfig | 2 +- include/linux/amba/bus.h | 11 +++++++++++ 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/platform/Kconfig b/drivers/vfio/platform/Kconfig index 233efde219cc10..ab341108a0be94 100644 --- a/drivers/vfio/platform/Kconfig +++ b/drivers/vfio/platform/Kconfig @@ -12,7 +12,7 @@ config VFIO_PLATFORM config VFIO_AMBA tristate "VFIO support for AMBA devices" - depends on VFIO_PLATFORM && ARM_AMBA + depends on VFIO_PLATFORM && (ARM_AMBA || COMPILE_TEST) help Support for ARM AMBA devices with VFIO. This is required to make use of ARM AMBA devices present on the system using the VFIO diff --git a/include/linux/amba/bus.h b/include/linux/amba/bus.h index 6cc93ab5b8096d..c68d87b8728362 100644 --- a/include/linux/amba/bus.h +++ b/include/linux/amba/bus.h @@ -105,8 +105,19 @@ extern struct bus_type amba_bustype; #define amba_get_drvdata(d) dev_get_drvdata(&d->dev) #define amba_set_drvdata(d,p) dev_set_drvdata(&d->dev, p) +#ifdef CONFIG_ARM_AMBA int amba_driver_register(struct amba_driver *); void amba_driver_unregister(struct amba_driver *); +#else +static inline int amba_driver_register(struct amba_driver *drv) +{ + return -EINVAL; +} +static inline void amba_driver_unregister(struct amba_driver *drv) +{ +} +#endif + struct amba_device *amba_device_alloc(const char *, resource_size_t, size_t); void amba_device_put(struct amba_device *); int amba_device_add(struct amba_device *, struct resource *); From b2b12db53507bc97d96f6b7cb279e831e5eafb00 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Thu, 4 Mar 2021 21:30:03 -0400 Subject: [PATCH 24/28] vfio: Depend on MMU VFIO_IOMMU_TYPE1 does not compile with !MMU: ../drivers/vfio/vfio_iommu_type1.c: In function 'follow_fault_pfn': ../drivers/vfio/vfio_iommu_type1.c:536:22: error: implicit declaration of function 'pte_write'; did you mean 'vfs_write'? [-Werror=implicit-function-declaration] So require it. Suggested-by: Cornelia Huck Signed-off-by: Jason Gunthorpe Message-Id: <0-v1-02cb5500df6e+78-vfio_no_mmu_jgg@nvidia.com> Signed-off-by: Alex Williamson --- drivers/vfio/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig index 90c0525b1e0cf4..67d0bf4efa1606 100644 --- a/drivers/vfio/Kconfig +++ b/drivers/vfio/Kconfig @@ -22,7 +22,7 @@ config VFIO_VIRQFD menuconfig VFIO tristate "VFIO Non-Privileged userspace driver framework" select IOMMU_API - select VFIO_IOMMU_TYPE1 if (X86 || S390 || ARM || ARM64) + select VFIO_IOMMU_TYPE1 if MMU && (X86 || S390 || ARM || ARM64) help VFIO provides a framework for secure userspace device drivers. See Documentation/driver-api/vfio.rst for more details. From 4ab4fcfce5b540227d80eb32f1db45ab615f7c92 Mon Sep 17 00:00:00 2001 From: Daniel Jordan Date: Mon, 8 Mar 2021 12:24:52 -0500 Subject: [PATCH 25/28] vfio/type1: fix vaddr_get_pfns() return in vfio_pin_page_external() vaddr_get_pfns() now returns the positive number of pfns successfully gotten instead of zero. vfio_pin_page_external() might return 1 to vfio_iommu_type1_pin_pages(), which will treat it as an error, if vaddr_get_pfns() is successful but vfio_pin_page_external() doesn't reach vfio_lock_acct(). Fix it up in vfio_pin_page_external(). Found by inspection. Fixes: be16c1fd99f4 ("vfio/type1: Change success value of vaddr_get_pfn()") Signed-off-by: Daniel Jordan Message-Id: <20210308172452.38864-1-daniel.m.jordan@oracle.com> Signed-off-by: Alex Williamson --- drivers/vfio/vfio_iommu_type1.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 12d9905b429fd5..be444407664af7 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -785,7 +785,12 @@ static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr, return -ENODEV; ret = vaddr_get_pfns(mm, vaddr, 1, dma->prot, pfn_base, pages); - if (ret == 1 && do_accounting && !is_invalid_reserved_pfn(*pfn_base)) { + if (ret != 1) + goto out; + + ret = 0; + + if (do_accounting && !is_invalid_reserved_pfn(*pfn_base)) { ret = vfio_lock_acct(dma, 1, true); if (ret) { put_pfn(*pfn_base, dma->prot); @@ -797,6 +802,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr, } } +out: mmput(mm); return ret; } From 34e49994d0dcdb2d31d4d2908d04f4e9ce57e4d7 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Mon, 15 Mar 2021 15:18:24 +0100 Subject: [PATCH 26/28] btrfs: fix slab cache flags for free space tree bitmap The free space tree bitmap slab cache is created with SLAB_RED_ZONE but that's a debugging flag and not always enabled. Also the other slabs are created with at least SLAB_MEM_SPREAD that we want as well to average the memory placement cost. Reported-by: Vlastimil Babka Fixes: 3acd48507dc4 ("btrfs: fix allocation of free space cache v1 bitmap pages") CC: stable@vger.kernel.org # 5.4+ Signed-off-by: David Sterba --- fs/btrfs/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index ea5ede619220cb..5092dea21448c7 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -9005,7 +9005,7 @@ int __init btrfs_init_cachep(void) btrfs_free_space_bitmap_cachep = kmem_cache_create("btrfs_free_space_bitmap", PAGE_SIZE, PAGE_SIZE, - SLAB_RED_ZONE, NULL); + SLAB_MEM_SPREAD, NULL); if (!btrfs_free_space_bitmap_cachep) goto fail; From dbcc7d57bffc0c8cac9dac11bec548597d59a6a5 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Thu, 11 Mar 2021 14:31:05 +0000 Subject: [PATCH 27/28] btrfs: fix race when cloning extent buffer during rewind of an old root While resolving backreferences, as part of a logical ino ioctl call or fiemap, we can end up hitting a BUG_ON() when replaying tree mod log operations of a root, triggering a stack trace like the following: ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.c:1210! invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 1 PID: 19054 Comm: crawl_335 Tainted: G W 5.11.0-2d11c0084b02-misc-next+ #89 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:__tree_mod_log_rewind+0x3b1/0x3c0 Code: 05 48 8d 74 10 (...) RSP: 0018:ffffc90001eb70b8 EFLAGS: 00010297 RAX: 0000000000000000 RBX: ffff88812344e400 RCX: ffffffffb28933b6 RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff88812344e42c RBP: ffffc90001eb7108 R08: 1ffff11020b60a20 R09: ffffed1020b60a20 R10: ffff888105b050f9 R11: ffffed1020b60a1f R12: 00000000000000ee R13: ffff8880195520c0 R14: ffff8881bc958500 R15: ffff88812344e42c FS: 00007fd1955e8700(0000) GS:ffff8881f5600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efdb7928718 CR3: 000000010103a006 CR4: 0000000000170ee0 Call Trace: btrfs_search_old_slot+0x265/0x10d0 ? lock_acquired+0xbb/0x600 ? btrfs_search_slot+0x1090/0x1090 ? free_extent_buffer.part.61+0xd7/0x140 ? free_extent_buffer+0x13/0x20 resolve_indirect_refs+0x3e9/0xfc0 ? lock_downgrade+0x3d0/0x3d0 ? __kasan_check_read+0x11/0x20 ? add_prelim_ref.part.11+0x150/0x150 ? lock_downgrade+0x3d0/0x3d0 ? __kasan_check_read+0x11/0x20 ? lock_acquired+0xbb/0x600 ? __kasan_check_write+0x14/0x20 ? do_raw_spin_unlock+0xa8/0x140 ? rb_insert_color+0x30/0x360 ? prelim_ref_insert+0x12d/0x430 find_parent_nodes+0x5c3/0x1830 ? resolve_indirect_refs+0xfc0/0xfc0 ? lock_release+0xc8/0x620 ? fs_reclaim_acquire+0x67/0xf0 ? lock_acquire+0xc7/0x510 ? lock_downgrade+0x3d0/0x3d0 ? lockdep_hardirqs_on_prepare+0x160/0x210 ? lock_release+0xc8/0x620 ? fs_reclaim_acquire+0x67/0xf0 ? lock_acquire+0xc7/0x510 ? poison_range+0x38/0x40 ? unpoison_range+0x14/0x40 ? trace_hardirqs_on+0x55/0x120 btrfs_find_all_roots_safe+0x142/0x1e0 ? find_parent_nodes+0x1830/0x1830 ? btrfs_inode_flags_to_xflags+0x50/0x50 iterate_extent_inodes+0x20e/0x580 ? tree_backref_for_extent+0x230/0x230 ? lock_downgrade+0x3d0/0x3d0 ? read_extent_buffer+0xdd/0x110 ? lock_downgrade+0x3d0/0x3d0 ? __kasan_check_read+0x11/0x20 ? lock_acquired+0xbb/0x600 ? __kasan_check_write+0x14/0x20 ? _raw_spin_unlock+0x22/0x30 ? __kasan_check_write+0x14/0x20 iterate_inodes_from_logical+0x129/0x170 ? iterate_inodes_from_logical+0x129/0x170 ? btrfs_inode_flags_to_xflags+0x50/0x50 ? iterate_extent_inodes+0x580/0x580 ? __vmalloc_node+0x92/0xb0 ? init_data_container+0x34/0xb0 ? init_data_container+0x34/0xb0 ? kvmalloc_node+0x60/0x80 btrfs_ioctl_logical_to_ino+0x158/0x230 btrfs_ioctl+0x205e/0x4040 ? __might_sleep+0x71/0xe0 ? btrfs_ioctl_get_supported_features+0x30/0x30 ? getrusage+0x4b6/0x9c0 ? __kasan_check_read+0x11/0x20 ? lock_release+0xc8/0x620 ? __might_fault+0x64/0xd0 ? lock_acquire+0xc7/0x510 ? lock_downgrade+0x3d0/0x3d0 ? lockdep_hardirqs_on_prepare+0x210/0x210 ? lockdep_hardirqs_on_prepare+0x210/0x210 ? __kasan_check_read+0x11/0x20 ? do_vfs_ioctl+0xfc/0x9d0 ? ioctl_file_clone+0xe0/0xe0 ? lock_downgrade+0x3d0/0x3d0 ? lockdep_hardirqs_on_prepare+0x210/0x210 ? __kasan_check_read+0x11/0x20 ? lock_release+0xc8/0x620 ? __task_pid_nr_ns+0xd3/0x250 ? lock_acquire+0xc7/0x510 ? __fget_files+0x160/0x230 ? __fget_light+0xf2/0x110 __x64_sys_ioctl+0xc3/0x100 do_syscall_64+0x37/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fd1976e2427 Code: 00 00 90 48 8b 05 (...) RSP: 002b:00007fd1955e5cf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd1955e5f40 RCX: 00007fd1976e2427 RDX: 00007fd1955e5f48 RSI: 00000000c038943b RDI: 0000000000000004 RBP: 0000000001000000 R08: 0000000000000000 R09: 00007fd1955e6120 R10: 0000557835366b00 R11: 0000000000000246 R12: 0000000000000004 R13: 00007fd1955e5f48 R14: 00007fd1955e5f40 R15: 00007fd1955e5ef8 Modules linked in: ---[ end trace ec8931a1c36e57be ]--- (gdb) l *(__tree_mod_log_rewind+0x3b1) 0xffffffff81893521 is in __tree_mod_log_rewind (fs/btrfs/ctree.c:1210). 1205 * the modification. as we're going backwards, we do the 1206 * opposite of each operation here. 1207 */ 1208 switch (tm->op) { 1209 case MOD_LOG_KEY_REMOVE_WHILE_FREEING: 1210 BUG_ON(tm->slot < n); 1211 fallthrough; 1212 case MOD_LOG_KEY_REMOVE_WHILE_MOVING: 1213 case MOD_LOG_KEY_REMOVE: 1214 btrfs_set_node_key(eb, &tm->key, tm->slot); Here's what happens to hit that BUG_ON(): 1) We have one tree mod log user (through fiemap or the logical ino ioctl), with a sequence number of 1, so we have fs_info->tree_mod_seq == 1; 2) Another task is at ctree.c:balance_level() and we have eb X currently as the root of the tree, and we promote its single child, eb Y, as the new root. Then, at ctree.c:balance_level(), we call: tree_mod_log_insert_root(eb X, eb Y, 1); 3) At tree_mod_log_insert_root() we create tree mod log elements for each slot of eb X, of operation type MOD_LOG_KEY_REMOVE_WHILE_FREEING each with a ->logical pointing to ebX->start. These are placed in an array named tm_list. Lets assume there are N elements (N pointers in eb X); 4) Then, still at tree_mod_log_insert_root(), we create a tree mod log element of operation type MOD_LOG_ROOT_REPLACE, ->logical set to ebY->start, ->old_root.logical set to ebX->start, ->old_root.level set to the level of eb X and ->generation set to the generation of eb X; 5) Then tree_mod_log_insert_root() calls tree_mod_log_free_eb() with tm_list as argument. After that, tree_mod_log_free_eb() calls __tree_mod_log_insert() for each member of tm_list in reverse order, from highest slot in eb X, slot N - 1, to slot 0 of eb X; 6) __tree_mod_log_insert() sets the sequence number of each given tree mod log operation - it increments fs_info->tree_mod_seq and sets fs_info->tree_mod_seq as the sequence number of the given tree mod log operation. This means that for the tm_list created at tree_mod_log_insert_root(), the element corresponding to slot 0 of eb X has the highest sequence number (1 + N), and the element corresponding to the last slot has the lowest sequence number (2); 7) Then, after inserting tm_list's elements into the tree mod log rbtree, the MOD_LOG_ROOT_REPLACE element is inserted, which gets the highest sequence number, which is N + 2; 8) Back to ctree.c:balance_level(), we free eb X by calling btrfs_free_tree_block() on it. Because eb X was created in the current transaction, has no other references and writeback did not happen for it, we add it back to the free space cache/tree; 9) Later some other task T allocates the metadata extent from eb X, since it is marked as free space in the space cache/tree, and uses it as a node for some other btree; 10) The tree mod log user task calls btrfs_search_old_slot(), which calls get_old_root(), and finally that calls __tree_mod_log_oldest_root() with time_seq == 1 and eb_root == eb Y; 11) First iteration of the while loop finds the tree mod log element with sequence number N + 2, for the logical address of eb Y and of type MOD_LOG_ROOT_REPLACE; 12) Because the operation type is MOD_LOG_ROOT_REPLACE, we don't break out of the loop, and set root_logical to point to tm->old_root.logical which corresponds to the logical address of eb X; 13) On the next iteration of the while loop, the call to tree_mod_log_search_oldest() returns the smallest tree mod log element for the logical address of eb X, which has a sequence number of 2, an operation type of MOD_LOG_KEY_REMOVE_WHILE_FREEING and corresponds to the old slot N - 1 of eb X (eb X had N items in it before being freed); 14) We then break out of the while loop and return the tree mod log operation of type MOD_LOG_ROOT_REPLACE (eb Y), and not the one for slot N - 1 of eb X, to get_old_root(); 15) At get_old_root(), we process the MOD_LOG_ROOT_REPLACE operation and set "logical" to the logical address of eb X, which was the old root. We then call tree_mod_log_search() passing it the logical address of eb X and time_seq == 1; 16) Then before calling tree_mod_log_search(), task T adds a key to eb X, which results in adding a tree mod log operation of type MOD_LOG_KEY_ADD to the tree mod log - this is done at ctree.c:insert_ptr() - but after adding the tree mod log operation and before updating the number of items in eb X from 0 to 1... 17) The task at get_old_root() calls tree_mod_log_search() and gets the tree mod log operation of type MOD_LOG_KEY_ADD just added by task T. Then it enters the following if branch: if (old_root && tm && tm->op != MOD_LOG_KEY_REMOVE_WHILE_FREEING) { (...) } (...) Calls read_tree_block() for eb X, which gets a reference on eb X but does not lock it - task T has it locked. Then it clones eb X while it has nritems set to 0 in its header, before task T sets nritems to 1 in eb X's header. From hereupon we use the clone of eb X which no other task has access to; 18) Then we call __tree_mod_log_rewind(), passing it the MOD_LOG_KEY_ADD mod log operation we just got from tree_mod_log_search() in the previous step and the cloned version of eb X; 19) At __tree_mod_log_rewind(), we set the local variable "n" to the number of items set in eb X's clone, which is 0. Then we enter the while loop, and in its first iteration we process the MOD_LOG_KEY_ADD operation, which just decrements "n" from 0 to (u32)-1, since "n" is declared with a type of u32. At the end of this iteration we call rb_next() to find the next tree mod log operation for eb X, that gives us the mod log operation of type MOD_LOG_KEY_REMOVE_WHILE_FREEING, for slot 0, with a sequence number of N + 1 (steps 3 to 6); 20) Then we go back to the top of the while loop and trigger the following BUG_ON(): (...) switch (tm->op) { case MOD_LOG_KEY_REMOVE_WHILE_FREEING: BUG_ON(tm->slot < n); fallthrough; (...) Because "n" has a value of (u32)-1 (4294967295) and tm->slot is 0. Fix this by taking a read lock on the extent buffer before cloning it at ctree.c:get_old_root(). This should be done regardless of the extent buffer having been freed and reused, as a concurrent task might be modifying it (while holding a write lock on it). Reported-by: Zygo Blaxell Link: https://lore.kernel.org/linux-btrfs/20210227155037.GN28049@hungrycats.org/ Fixes: 834328a8493079 ("Btrfs: tree mod log's old roots could still be part of the tree") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/ctree.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index d56730a6788537..34b929bd5c1af5 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1365,7 +1365,9 @@ get_old_root(struct btrfs_root *root, u64 time_seq) "failed to read tree block %llu from get_old_root", logical); } else { + btrfs_tree_read_lock(old); eb = btrfs_clone_extent_buffer(old); + btrfs_tree_read_unlock(old); free_extent_buffer(old); } } else if (old_root) { From 485df75554257e883d0ce39bb886e8212349748e Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Thu, 11 Mar 2021 14:31:06 +0000 Subject: [PATCH 28/28] btrfs: always pin deleted leaves when there are active tree mod log users When freeing a tree block we may end up adding its extent back to the free space cache/tree, as long as there are no more references for it, it was created in the current transaction and writeback for it never happened. This is generally fine, however when we have tree mod log operations it can result in inconsistent versions of a btree after unwinding extent buffers with the recorded tree mod log operations. This is because: * We only log operations for nodes (adding and removing key/pointers), for leaves we don't do anything; * This means that we can log a MOD_LOG_KEY_REMOVE_WHILE_FREEING operation for a node that points to a leaf that was deleted; * Before we apply the logged operation to unwind a node, we can have that leaf's extent allocated again, either as a node or as a leaf, and possibly for another btree. This is possible if the leaf was created in the current transaction and writeback for it never started, in which case btrfs_free_tree_block() returns its extent back to the free space cache/tree; * Then, before applying the tree mod log operation, some task allocates the metadata extent just freed before, and uses it either as a leaf or as a node for some btree (can be the same or another one, it does not matter); * After applying the MOD_LOG_KEY_REMOVE_WHILE_FREEING operation we now get the target node with an item pointing to the metadata extent that now has content different from what it had before the leaf was deleted. It might now belong to a different btree and be a node and not a leaf anymore. As a consequence, the results of searches after the unwinding can be unpredictable and produce unexpected results. So make sure we pin extent buffers corresponding to leaves when there are tree mod log users. CC: stable@vger.kernel.org # 4.14+ Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/extent-tree.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 78ad31a59e59e0..36a3c973fda102 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -3323,6 +3323,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, if (last_ref && btrfs_header_generation(buf) == trans->transid) { struct btrfs_block_group *cache; + bool must_pin = false; if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) { ret = check_ref_cleanup(trans, buf->start); @@ -3340,7 +3341,27 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, goto out; } - if (btrfs_is_zoned(fs_info)) { + /* + * If this is a leaf and there are tree mod log users, we may + * have recorded mod log operations that point to this leaf. + * So we must make sure no one reuses this leaf's extent before + * mod log operations are applied to a node, otherwise after + * rewinding a node using the mod log operations we get an + * inconsistent btree, as the leaf's extent may now be used as + * a node or leaf for another different btree. + * We are safe from races here because at this point no other + * node or root points to this extent buffer, so if after this + * check a new tree mod log user joins, it will not be able to + * find a node pointing to this leaf and record operations that + * point to this leaf. + */ + if (btrfs_header_level(buf) == 0) { + read_lock(&fs_info->tree_mod_log_lock); + must_pin = !list_empty(&fs_info->tree_mod_seq_list); + read_unlock(&fs_info->tree_mod_log_lock); + } + + if (must_pin || btrfs_is_zoned(fs_info)) { btrfs_redirty_list_add(trans->transaction, buf); pin_down_extent(trans, cache, buf->start, buf->len, 1); btrfs_put_block_group(cache);