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BUG: KCSAN: data-race in __mark_inode_dirty / move_expired_inodes

read-write to 0xffff88811947a008 of 4 bytes by task 557 on cpu 0:
 move_expired_inodes+0x17a/0x400 fs/fs-writeback.c:1457
 queue_io+0xd9/0x2c0 fs/fs-writeback.c:1509
 wb_writeback+0x226/0x5c0 fs/fs-writeback.c:2152
 wb_do_writeback fs/fs-writeback.c:2303 [inline]
 wb_workfn+0x194/0x910 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3319
 worker_thread+0x582/0x770 kernel/workqueue.c:3400
 kthread+0x486/0x510 kernel/kthread.c:463
 ret_from_fork+0xdd/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff88811947a008 of 4 bytes by task 5779 on cpu 1:
 __mark_inode_dirty+0x18e/0x760 fs/fs-writeback.c:2549
 mark_buffer_dirty+0x133/0x210 fs/buffer.c:1209
 block_commit_write fs/buffer.c:2218 [inline]
 block_write_end+0x12d/0x210 fs/buffer.c:2294
 ext4_write_end+0x134/0x720 fs/ext4/inode.c:1448
 ext4_da_write_end+0x65/0x800 fs/ext4/inode.c:3277
 generic_perform_write+0x312/0x490 mm/filemap.c:4196
 ext4_buffered_write_iter+0x1ee/0x3c0 fs/ext4/file.c:299
 ext4_dio_write_iter fs/ext4/file.c:613 [inline]
 ext4_file_write_iter+0xdbf/0xf00 fs/ext4/file.c:721
 iter_file_splice_write+0x5ef/0x970 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x153/0x2a0 fs/splice.c:1158
 splice_direct_to_actor+0x30f/0x680 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xda/0x150 fs/splice.c:1227
 do_sendfile+0x380/0x650 fs/read_write.c:1370
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64 fs/read_write.c:1417 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1417
 x64_sys_call+0x2bb0/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000028 -> 0x0001002a

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5779 Comm: syz.1.728 Not tainted 6.16.0-syzkaller-11699-g7e161a991ea7 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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