EXT4-fs (loop2): 1 truncate cleaned up
EXT4-fs (loop2): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
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BUG: KCSAN: data-race in __mark_inode_dirty / writeback_single_inode

write to 0xffff888105977a18 of 4 bytes by task 7025 on cpu 0:
 writeback_single_inode+0x14a/0x3e0 fs/fs-writeback.c:1798
 sync_inode_metadata+0x5b/0x90 fs/fs-writeback.c:2883
 generic_buffers_fsync_noflush+0xd9/0x120 fs/buffer.c:619
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1ab/0x690 fs/ext4/fsync.c:147
 vfs_fsync_range fs/sync.c:187 [inline]
 vfs_fsync fs/sync.c:201 [inline]
 do_fsync fs/sync.c:212 [inline]
 __do_sys_fdatasync fs/sync.c:222 [inline]
 __se_sys_fdatasync fs/sync.c:220 [inline]
 __x64_sys_fdatasync+0x83/0xe0 fs/sync.c:220
 x64_sys_call+0x2f83/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:76
 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 0xffff888105977a18 of 4 bytes by task 7018 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
 generic_perform_write+0x30f/0x490 mm/filemap.c:4196
 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+0x4a0/0x8e0 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

value changed: 0x00000038 -> 0x00000022

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7018 Comm: syz.2.910 Not tainted 6.16.0-syzkaller-12016-gbec077162bd0 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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