[moderation] [ext4?] KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (10)

Hello,

syzbot found the following issue on:

HEAD commit: 0fed89a961ea Merge tag 'hyperv-fixes-signed-20250311' of g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=151f1874580000
kernel config: https://syzkaller.appspot.com/x/.config?x=958433697845b9a6
dashboard link: https://syzkaller.appspot.com/bug?extid=f717b3f6e17118e4561e
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [[email protected] [email protected] [email protected] [email protected]]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/df025c06d4ff/disk-0fed89a9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1a8f6a6f94df/vmlinux-0fed89a9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ad51e6db63d1/bzImage-0fed89a9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]

==================================================================
BUG: KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked

read-write to 0xffff888104a4aa38 of 4 bytes by task 88 on cpu 0:
redirty_tail_locked+0x54/0x270 fs/fs-writeback.c:1373
requeue_inode fs/fs-writeback.c:1638 [inline]
writeback_sb_inodes+0x6e6/0xa30 fs/fs-writeback.c:2005
wb_writeback+0x262/0x640 fs/fs-writeback.c:2156
wb_do_writeback fs/fs-writeback.c:2303 [inline]
wb_workfn+0x1a8/0x940 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x4db/0xa20 kernel/workqueue.c:3319
worker_thread+0x51d/0x6f0 kernel/workqueue.c:3400
kthread+0x4ae/0x520 kernel/kthread.c:464
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff888104a4aa38 of 4 bytes by task 15777 on cpu 1:
__mark_inode_dirty+0x198/0x7e0 fs/fs-writeback.c:2537
mark_buffer_dirty+0x149/0x230 fs/buffer.c:1199
__block_commit_write fs/buffer.c:2189 [inline]
block_page_mkwrite+0x29c/0x3f0 fs/buffer.c:2633
ext4_page_mkwrite+0x73d/0xb70 fs/ext4/inode.c:6181
do_page_mkwrite mm/memory.c:3257 [inline]
do_shared_fault mm/memory.c:5486 [inline]
do_fault mm/memory.c:5548 [inline]
do_pte_missing mm/memory.c:4060 [inline]
handle_pte_fault mm/memory.c:5907 [inline]
__handle_mm_fault mm/memory.c:6050 [inline]
handle_mm_fault+0x12f7/0x2ac0 mm/memory.c:6219
do_user_addr_fault arch/x86/mm/fault.c:1337 [inline]
handle_page_fault arch/x86/mm/fault.c:1480 [inline]
exc_page_fault+0x3b9/0x650 arch/x86/mm/fault.c:1538
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

value changed: 0x00010002 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 15777 Comm: syz.5.4372 Tainted: G W 6.14.0-rc6-syzkaller-00016-g0fed89a961ea #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================


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