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KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (10)

Status: moderation: reported on 2025/03/12 23:32
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+f717b3f6e17118e4561e@syzkaller.appspotmail.com
First crash: 52d, last: 52d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (4) ext4 1 515d 514d 0/28 auto-obsoleted due to no activity on 2024/01/09 20:12
upstream KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (7) ext4 1 328d 328d 0/28 auto-obsoleted due to no activity on 2024/07/15 04:44
upstream KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (2) ext4 10 618d 753d 0/28 auto-obsoleted due to no activity on 2023/09/29 00:10
upstream KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (5) ext4 1 460d 460d 0/28 auto-obsoleted due to no activity on 2024/03/05 08:43
upstream KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (9) ext4 exfat 2 137d 190d 0/28 auto-obsoleted due to no activity on 2025/02/12 04:51
upstream KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (3) ext4 3 553d 579d 0/28 auto-obsoleted due to no activity on 2023/12/02 13:09
upstream KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (6) ext4 1 400d 400d 0/28 auto-obsoleted due to no activity on 2024/05/04 07:48
upstream KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked (8) exfat 1 269d 269d 0/28 auto-obsoleted due to no activity on 2024/09/11 16:13
upstream KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked ext4 1 821d 821d 0/28 auto-obsoleted due to no activity on 2023/03/31 02:53

Sample crash report:
==================================================================
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
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/12 23:31 upstream 0fed89a961ea 1a5d9317 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __mark_inode_dirty / redirty_tail_locked
* Struck through repros no longer work on HEAD.