==================================================================
BUG: KCSAN: data-race in __ext4_update_other_inode_time / writeback_single_inode

write to 0xffff888105b98660 of 8 bytes by task 25137 on cpu 0:
 writeback_single_inode+0x148/0x3e0 fs/fs-writeback.c:1723
 sync_inode fs/fs-writeback.c:2745 [inline]
 sync_inode_metadata+0x57/0x80 fs/fs-writeback.c:2765
 ext4_fsync_nojournal fs/ext4/fsync.c:92 [inline]
 ext4_sync_file+0x359/0x670 fs/ext4/fsync.c:170
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2948 [inline]
 iomap_dio_complete+0x2d5/0x3c0 fs/iomap/direct-io.c:127
 iomap_dio_rw+0x4e/0x70 fs/iomap/direct-io.c:652
 ext4_dio_write_iter fs/ext4/file.c:568 [inline]
 ext4_file_write_iter+0xa5e/0x11a0 fs/ext4/file.c:678
 call_write_iter include/linux/fs.h:2157 [inline]
 do_iter_readv_writev+0x2cd/0x370 fs/read_write.c:729
 do_iter_write+0x192/0x5c0 fs/read_write.c:855
 vfs_iter_write+0x4c/0x70 fs/read_write.c:896
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x618/0xb90 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1314 [inline]
 __se_sys_sendfile64 fs/read_write.c:1300 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1300
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888105b98660 of 8 bytes by task 25143 on cpu 1:
 inode_is_dirtytime_only include/linux/fs.h:2465 [inline]
 __ext4_update_other_inode_time+0x48/0x5c0 fs/ext4/inode.c:4962
 ext4_update_other_inodes_time fs/ext4/inode.c:5005 [inline]
 ext4_do_update_inode fs/ext4/inode.c:5134 [inline]
 ext4_mark_iloc_dirty+0x12b6/0x1750 fs/ext4/inode.c:5723
 __ext4_mark_inode_dirty+0x4db/0x5b0 fs/ext4/inode.c:5917
 ext4_dirty_inode+0x86/0xa0 fs/ext4/inode.c:5946
 __mark_inode_dirty+0x77/0x6a0 fs/fs-writeback.c:2398
 mark_inode_dirty include/linux/fs.h:2446 [inline]
 dquot_alloc_space include/linux/quotaops.h:317 [inline]
 dquot_alloc_block include/linux/quotaops.h:334 [inline]
 ext4_mb_new_blocks+0x116b/0x1f90 fs/ext4/mballoc.c:5477
 ext4_ext_map_blocks+0x1569/0x1f00 fs/ext4/extents.c:4245
 ext4_map_blocks+0x70d/0xef0 fs/ext4/inode.c:638
 ext4_getblk+0xb1/0x3d0 fs/ext4/inode.c:848
 ext4_bread+0x28/0x100 fs/ext4/inode.c:900
 ext4_append+0xd1/0x1c0 fs/ext4/namei.c:67
 ext4_init_new_dir+0x177/0x500 fs/ext4/namei.c:2885
 ext4_mkdir+0x329/0x760 fs/ext4/namei.c:2931
 vfs_mkdir+0x2c3/0x3e0 fs/namei.c:3854
 do_mkdirat+0x12e/0x2e0 fs/namei.c:3880
 __do_sys_mkdir fs/namei.c:3900 [inline]
 __se_sys_mkdir fs/namei.c:3898 [inline]
 __x64_sys_mkdir+0x40/0x50 fs/namei.c:3898
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000007 -> 0x0000000000000080

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 25143 Comm: syz-executor.2 Tainted: G        W         5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
EXT4-fs error (device loop2): __ext4_iget:4846: inode #2: block 3646141627: comm syz-executor.2: invalid block
EXT4-fs (loop2): get root inode failed
EXT4-fs (loop2): mount failed
loop2: detected capacity change from 0 to 512
EXT4-fs error (device loop2): __ext4_iget:4846: inode #2: block 3646141627: comm syz-executor.2: invalid block
EXT4-fs (loop2): get root inode failed
EXT4-fs (loop2): mount failed