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BUG: KCSAN: data-race in __mark_inode_dirty / __writeback_single_inode

read-write to 0xffff8881076bcea8 of 4 bytes by task 52 on cpu 0:
 __writeback_single_inode+0x1e3/0x7c0 fs/fs-writeback.c:1755
 writeback_sb_inodes+0x48f/0xa30 fs/fs-writeback.c:2015
 wb_writeback+0x252/0x5c0 fs/fs-writeback.c:2195
 wb_do_writeback fs/fs-writeback.c:2342 [inline]
 wb_workfn+0x194/0x910 fs/fs-writeback.c:2382
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346
 worker_thread+0x582/0x770 kernel/workqueue.c:3427
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x122/0x1b0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff8881076bcea8 of 4 bytes by task 3304 on cpu 1:
 __mark_inode_dirty+0x191/0x750 fs/fs-writeback.c:2588
 generic_update_time fs/inode.c:2105 [inline]
 inode_update_time fs/inode.c:2118 [inline]
 __file_update_time fs/inode.c:2345 [inline]
 file_update_time+0x288/0x2b0 fs/inode.c:2375
 ext4_page_mkwrite+0x18c/0xb90 fs/ext4/inode.c:6683
 do_page_mkwrite mm/memory.c:3488 [inline]
 wp_page_shared mm/memory.c:3889 [inline]
 do_wp_page+0xa77/0x2510 mm/memory.c:4108
 handle_pte_fault mm/memory.c:6193 [inline]
 __handle_mm_fault mm/memory.c:6318 [inline]
 handle_mm_fault+0x77d/0x2be0 mm/memory.c:6487
 do_user_addr_fault+0x630/0x1080 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618

value changed: 0x00020052 -> 0x00000040

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3304 Comm: syz-executor Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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