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BUG: KCSAN: data-race in other_inode_match / writeback_single_inode

read to 0xffff8881250ae180 of 8 bytes by task 15095 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_split_extent_at+0x277/0x910 fs/ext4/extents.c:3383
 ext4_force_split_extent_at fs/ext4/extents.c:306 [inline]
 ext4_swap_extents+0x4f5/0xe10 fs/ext4/extents.c:5922
 move_extent_per_page fs/ext4/move_extent.c:339 [inline]
 ext4_move_extents+0x1244/0x1e40 fs/ext4/move_extent.c:673
 ext4_ioctl+0x2b73/0x3290 fs/ext4/ioctl.c:992
 vfs_ioctl fs/ioctl.c:47 [inline]
 file_ioctl fs/ioctl.c:545 [inline]
 do_vfs_ioctl+0x84f/0xcf0 fs/ioctl.c:732
 ksys_ioctl+0xbd/0xe0 fs/ioctl.c:749
 __do_sys_ioctl fs/ioctl.c:756 [inline]
 __se_sys_ioctl fs/ioctl.c:754 [inline]
 __x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:754
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8881250ae180 of 8 bytes by task 15093 on cpu 1:
 writeback_single_inode+0x214/0x310 fs/fs-writeback.c:1562
 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
 iter_file_splice_write+0x530/0x840 fs/splice.c:760
 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:1519 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0xbe/0x140 fs/read_write.c:1511
 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: 1 PID: 15093 Comm: syz-executor.0 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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