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BUG: KCSAN: data-race in __mark_inode_dirty / __mark_inode_dirty

write to 0xffff888107ffbac8 of 8 bytes by task 6321 on cpu 0:
 __mark_inode_dirty+0x250/0x7d0 fs/fs-writeback.c:2483
 fat_update_time+0x1fe/0x210 fs/fat/misc.c:357
 inode_update_time fs/inode.c:1955 [inline]
 __file_update_time fs/inode.c:2144 [inline]
 file_update_time+0xac/0x140 fs/inode.c:2174
 __generic_file_write_iter+0x4f/0x120 mm/filemap.c:4003
 generic_file_write_iter+0x7d/0x1c0 mm/filemap.c:4048
 do_iter_write+0x4ad/0x770 fs/read_write.c:860
 vfs_iter_write+0x56/0x70 fs/read_write.c:901
 iter_file_splice_write+0x462/0x7e0 fs/splice.c:736
 do_splice_from fs/splice.c:933 [inline]
 direct_splice_actor+0x8a/0xb0 fs/splice.c:1142
 splice_direct_to_actor+0x31d/0x690 fs/splice.c:1088
 do_splice_direct+0x10d/0x190 fs/splice.c:1194
 do_sendfile+0x3c4/0x980 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1316 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0xbd/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888107ffbac8 of 8 bytes by task 6333 on cpu 1:
 __mark_inode_dirty+0x199/0x7d0 fs/fs-writeback.c:2474
 fat_update_time+0x1fe/0x210 fs/fat/misc.c:357
 inode_update_time fs/inode.c:1955 [inline]
 touch_atime+0x147/0x2d0 fs/inode.c:2028
 file_accessed include/linux/fs.h:2360 [inline]
 filemap_splice_read+0x76e/0x7f0 mm/filemap.c:2925
 vfs_splice_read fs/splice.c:993 [inline]
 splice_direct_to_actor+0x28c/0x690 fs/splice.c:1069
 do_splice_direct+0x10d/0x190 fs/splice.c:1194
 do_sendfile+0x3c4/0x980 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000000 -> 0x0000000000000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 6333 Comm: syz-executor.1 Not tainted 6.7.0-rc7-syzkaller-00029-g8735c7c84d1b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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