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BUG: KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers

write to 0xffff88810abcaf60 of 8 bytes by task 32622 on cpu 0:
 __remove_assoc_queue fs/buffer.c:524 [inline]
 fsync_buffers_list fs/buffer.c:728 [inline]
 sync_mapping_buffers+0x165/0x7d0 fs/buffer.c:591
 fat_file_fsync+0xad/0x100 fs/fat/file.c:195
 vfs_fsync_range+0x10b/0x120 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2452 [inline]
 generic_file_write_iter+0x191/0x1c0 mm/filemap.c:4090
 call_write_iter include/linux/fs.h:1851 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x463/0x760 fs/read_write.c:584
 ksys_write+0xeb/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88810abcaf60 of 8 bytes by task 32639 on cpu 1:
 mark_buffer_dirty_inode+0x96/0x1c0 fs/buffer.c:624
 fat_mirror_bhs+0x212/0x310 fs/fat/fatent.c:398
 fat_alloc_clusters+0x973/0xa60 fs/fat/fatent.c:543
 fat_add_cluster+0x47/0xd0 fs/fat/inode.c:108
 fat_fallocate+0x129/0x1d0 fs/fat/file.c:292
 vfs_fallocate+0x369/0x3d0 fs/open.c:324
 do_vfs_ioctl+0x12a1/0x1360 fs/ioctl.c:849
 __do_sys_ioctl fs/ioctl.c:868 [inline]
 __se_sys_ioctl+0x81/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0xffff88810abd3890 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 32639 Comm: syz-executor.2 Not tainted 6.3.0-syzkaller-04626-g0cfd8703e7da #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
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