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BUG: KCSAN: data-race in __mark_inode_dirty / __writeback_single_inode

read-write to 0xffff8881075be008 of 4 bytes by task 11794 on cpu 1:
 __writeback_single_inode+0x1e3/0x7c0 fs/fs-writeback.c:1716
 writeback_sb_inodes+0x480/0xa20 fs/fs-writeback.c:1976
 wb_writeback+0x252/0x5c0 fs/fs-writeback.c:2156
 wb_do_writeback fs/fs-writeback.c:2303 [inline]
 wb_workfn+0x194/0x910 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3321
 worker_thread+0x582/0x770 kernel/workqueue.c:3402
 kthread+0x486/0x510 kernel/kthread.c:464
 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff8881075be008 of 4 bytes by task 19009 on cpu 0:
 __mark_inode_dirty+0x18e/0x760 fs/fs-writeback.c:2549
 generic_update_time fs/inode.c:2064 [inline]
 inode_update_time fs/inode.c:2077 [inline]
 __file_update_time fs/inode.c:2305 [inline]
 file_update_time+0x288/0x2b0 fs/inode.c:2335
 ext4_page_mkwrite+0x18b/0xba0 fs/ext4/inode.c:6577
 do_page_mkwrite mm/memory.c:3378 [inline]
 wp_page_shared mm/memory.c:3779 [inline]
 do_wp_page+0xe5a/0x2400 mm/memory.c:3998
 handle_pte_fault mm/memory.c:6105 [inline]
 __handle_mm_fault mm/memory.c:6232 [inline]
 handle_mm_fault+0x77d/0x2be0 mm/memory.c:6401
 do_user_addr_fault+0x636/0x1090 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:623

value changed: 0x0001002a -> 0x00000002

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 19009 Comm: syz.1.10368 Tainted: G        W           6.16.0-rc1-syzkaller-00003-gf09079bd04a9 #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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