[Deepin-Kernel-SIG] [linux 6.6-y] [Upstream] block: fix 'kmem_cache of name 'bio-108' already exists'

[opsiff]

mainline inclusion
from mainline-v6.14-rc5
category: bugfix

Device mapper bioset often has big bio_slab size, which can be more than 1000, then 8byte can't hold the slab name any more, cause the kmem_cache allocation warning of 'kmem_cache of name 'bio-108' already exists'.

Fix the warning by extending bio_slab->name to 12 bytes, but fix output of /proc/slabinfo

Reported-by: Guangwu Zhang guazhang@redhat.com

Link: https://lore.kernel.org/r/20250228132656.2838008-1-ming.lei@redhat.com

(cherry picked from commit b654f7a)

Summary by Sourcery

Bug Fixes:

• Fixes kmem_cache allocation warning of 'kmem_cache of name 'bio-108' already exists' by extending bio_slab->name to 12 bytes.

[sourcery-ai]

Reviewer's Guide by Sourcery

This pull request addresses a kmem_cache allocation warning caused by the bio_slab name field being too small for large slab sizes. The name field in the bio_slab struct has been increased from 8 to 12 bytes to resolve this issue.

Updated class diagram for bio_slab struct

classDiagram
  class bio_slab {
    struct kmem_cache* slab
    unsigned int slab_ref
    unsigned int slab_size
    char name[12]
  }
  note for bio_slab "'name' field increased from 8 to 12 bytes"

Loading

File-Level Changes

Change	Details	Files
Increased the size of the name field in the bio_slab structure to accommodate larger slab sizes and prevent kmem_cache allocation warnings.	Increased the size of the name field in the bio_slab struct from 8 bytes to 12 bytes.	block/bio.c

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[deepin-ci-robot]

deepin pr auto review

关键摘要:

• bio_slab 结构体中的 name 字段从 8 字节扩展到 12 字节，需要确认是否有足够的理由来支持这一变化，例如是否需要存储更长的名称。

是否建议立即修改:

• 是，如果扩展 name 字段是为了满足新的需求，需要确保这一变化不会导致其他问题，例如内存使用增加、数据截断等。同时，需要检查所有使用 bio_slab 结构体的地方，确保它们能够正确处理新的字段长度。

[sourcery-ai]

Hey @opsiff - I've reviewed your changes - here's some feedback:

Overall Comments:

• Consider adding a comment explaining why the size was increased to 12 bytes specifically.

Here's what I looked at during the review

• 🟢 General issues: all looks good
• 🟢 Security: all looks good
• 🟢 Testing: all looks good
• 🟢 Complexity: all looks good
• 🟢 Documentation: all looks good

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[winnscode]

lgtm :)

[deepin-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: winnscode
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