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BUG: KCSAN: data-race in inode_sync_complete / other_inode_match

write to 0xffff888128e801c0 of 8 bytes by task 21041 on cpu 1:
 inode_sync_complete+0x3a/0x70 fs/fs-writeback.c:1197
 writeback_single_inode+0x293/0x310 fs/fs-writeback.c:1578
 sync_inode fs/fs-writeback.c:2602 [inline]
 sync_inode_metadata+0x74/0xa0 fs/fs-writeback.c:2622
 ext4_fsync_nojournal fs/ext4/fsync.c:94 [inline]
 ext4_sync_file+0x4b5/0xaf0 fs/ext4/fsync.c:172
 vfs_fsync_range+0x82/0x150 fs/sync.c:197
 generic_write_sync include/linux/fs.h:2856 [inline]
 ext4_buffered_write_iter+0x222/0x290 fs/ext4/file.c:259
 ext4_file_write_iter+0xf4/0xd40 fs/ext4/file.c:547
 call_write_iter include/linux/fs.h:1902 [inline]
 do_iter_readv_writev+0x487/0x5b0 fs/read_write.c:693
 do_iter_write fs/read_write.c:970 [inline]
 do_iter_write+0x13b/0x3c0 fs/read_write.c:951
 vfs_iter_write+0x5c/0x80 fs/read_write.c:983
 ovl_write_iter+0x366/0x550 fs/overlayfs/file.c:278
 call_write_iter include/linux/fs.h:1902 [inline]
 new_sync_write+0x388/0x4a0 fs/read_write.c:483
 __vfs_write+0xb1/0xc0 fs/read_write.c:496
 __kernel_write+0xb8/0x240 fs/read_write.c:515
 write_pipe_buf+0xb6/0xf0 fs/splice.c:809
 splice_from_pipe_feed fs/splice.c:512 [inline]
 __splice_from_pipe+0x295/0x4a0 fs/splice.c:636
 splice_from_pipe+0xbb/0x100 fs/splice.c:671
 default_file_splice_write+0x45/0x90 fs/splice.c:821
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0xa0/0xc0 fs/splice.c:1037
 splice_direct_to_actor+0x22b/0x540 fs/splice.c:992
 do_splice_direct+0x161/0x1e0 fs/splice.c:1080
 do_sendfile+0x384/0x7f0 fs/read_write.c:1464
 __do_sys_sendfile64 fs/read_write.c:1525 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0x12a/0x140 fs/read_write.c:1511
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888128e801c0 of 8 bytes by task 21055 on cpu 0:
 other_inode_match+0x6b/0x5c0 fs/ext4/inode.c:4820
 find_inode_nowait+0x135/0x160 fs/inode.c:1437
 ext4_update_other_inodes_time fs/ext4/inode.c:4868 [inline]
 ext4_do_update_inode fs/ext4/inode.c:4994 [inline]
 ext4_mark_iloc_dirty+0x12a8/0x1580 fs/ext4/inode.c:5547
 ext4_mark_inode_dirty+0xe9/0x420 fs/ext4/inode.c:5740
 __ext4_ext_dirty+0xfc/0x120 fs/ext4/extents.c:177
 ext4_ext_insert_extent+0x9cd/0x25c0 fs/ext4/extents.c:2167
 ext4_ext_map_blocks+0xc52/0x2320 fs/ext4/extents.c:4507
 ext4_map_blocks+0x23a/0xff0 fs/ext4/inode.c:623
 ext4_getblk+0x82/0x380 fs/ext4/inode.c:827
 ext4_bread+0x4a/0x210 fs/ext4/inode.c:877
 ext4_append+0xc8/0x1f0 fs/ext4/namei.c:67
 ext4_init_new_dir fs/ext4/namei.c:2739 [inline]
 ext4_mkdir+0x405/0x820 fs/ext4/namei.c:2784
 vfs_mkdir+0x283/0x390 fs/namei.c:3819
 do_mkdirat+0x1ac/0x1f0 fs/namei.c:3842
 __do_sys_mkdir fs/namei.c:3858 [inline]
 __se_sys_mkdir fs/namei.c:3856 [inline]
 __x64_sys_mkdir+0x40/0x50 fs/namei.c:3856
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 21055 Comm: syz-executor.2 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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