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BUG: KCSAN: data-race in __mark_inode_dirty / __writeback_single_inode

write to 0xffff88810049a008 of 4 bytes by task 7316 on cpu 0:
 __mark_inode_dirty+0x248/0x750 fs/fs-writeback.c:2558
 ext4_mb_new_blocks+0x10b9/0x2080 fs/ext4/mballoc.c:-1
 ext4_ext_map_blocks+0xff5/0x38a0 fs/ext4/extents.c:4383
 ext4_map_create_blocks fs/ext4/inode.c:609 [inline]
 ext4_map_blocks+0x5ee/0xd00 fs/ext4/inode.c:811
 _ext4_get_block+0x10a/0x350 fs/ext4/inode.c:910
 ext4_get_block_unwritten+0x2a/0xb0 fs/ext4/inode.c:943
 ext4_block_write_begin+0x5e5/0xc00 fs/ext4/inode.c:1198
 ext4_write_begin+0x647/0xeb0 fs/ext4/ext4_jbd2.h:-1
 ext4_da_write_begin+0x1fb/0x6e0 fs/ext4/inode.c:3129
 generic_perform_write+0x184/0x490 mm/filemap.c:4175
 ext4_buffered_write_iter+0x1ee/0x3c0 fs/ext4/file.c:299
 ext4_file_write_iter+0x383/0xf00 fs/ext4/file.c:-1
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x527/0x960 fs/read_write.c:686
 ksys_write+0xda/0x1a0 fs/read_write.c:738
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:746
 x64_sys_call+0x27fe/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:2
 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

read to 0xffff88810049a008 of 4 bytes by task 31 on cpu 1:
 __writeback_single_inode+0x109/0x7c0 fs/fs-writeback.c:1700
 writeback_sb_inodes+0x48f/0xa30 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:3236 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3319
 worker_thread+0x582/0x770 kernel/workqueue.c:3400
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x11f/0x1b0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00010022 -> 0x0001003a

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 31 Comm: kworker/u8:1 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: writeback wb_workfn (flush-7:4)
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