KCSAN: data-race in __ext4_update_other_inode_time / vfs_fsync_range (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 127c501a Merge tag '5.10-rc5-smb3-fixes' of git://git.samb..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=137ee0e9500000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9b19d1bde60f8d
dashboard link: https://syzkaller.appspot.com/bug?extid=f4b9a7e9e6165b2f8ad0
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [adilger...@dilger.ca linux...@vger.kernel.org linux-...@vger.kernel.org ty...@mit.edu]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f4b9a7...@syzkaller.appspotmail.com

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

write to 0xffff88810d508c58 of 8 bytes by task 25958 on cpu 0:
__ext4_update_other_inode_time+0xc1/0x550 fs/ext4/inode.c:4966
ext4_update_other_inodes_time fs/ext4/inode.c:5002 [inline]
ext4_do_update_inode fs/ext4/inode.c:5131 [inline]
ext4_mark_iloc_dirty+0x1286/0x1650 fs/ext4/inode.c:5712
__ext4_mark_inode_dirty+0x450/0x610 fs/ext4/inode.c:5906
ext4_dirty_inode+0xa6/0xc0 fs/ext4/inode.c:5942
__mark_inode_dirty+0x74/0x740 fs/fs-writeback.c:2260
mark_inode_dirty_sync include/linux/fs.h:2188 [inline]
vfs_fsync_range+0xd6/0x120 fs/sync.c:199
generic_write_sync include/linux/fs.h:2739 [inline]
ext4_buffered_write_iter+0x384/0x3d0 fs/ext4/file.c:278
ext4_file_write_iter+0x45e/0x1090 fs/ext4/file.c:503
call_write_iter include/linux/fs.h:1903 [inline]
do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
do_iter_write+0x112/0x4b0 fs/read_write.c:866
vfs_iter_write+0x4c/0x70 fs/read_write.c:907
iter_file_splice_write+0x42a/0x780 fs/splice.c:686
do_splice_from fs/splice.c:764 [inline]
direct_splice_actor+0x80/0xa0 fs/splice.c:933
splice_direct_to_actor+0x345/0x650 fs/splice.c:888
do_splice_direct+0xf5/0x170 fs/splice.c:976
do_sendfile+0x5db/0xca0 fs/read_write.c:1257
__do_sys_sendfile64 fs/read_write.c:1312 [inline]
__se_sys_sendfile64 fs/read_write.c:1304 [inline]
__x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1304
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88810d508c58 of 8 bytes by task 25957 on cpu 1:
vfs_fsync_range+0x98/0x120 fs/sync.c:198
generic_write_sync include/linux/fs.h:2739 [inline]
ext4_buffered_write_iter+0x384/0x3d0 fs/ext4/file.c:278
ext4_file_write_iter+0x45e/0x1090 fs/ext4/file.c:503
call_write_iter include/linux/fs.h:1903 [inline]
do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
do_iter_write+0x112/0x4b0 fs/read_write.c:866
vfs_iter_write+0x4c/0x70 fs/read_write.c:907
iter_file_splice_write+0x42a/0x780 fs/splice.c:686
do_splice_from fs/splice.c:764 [inline]
direct_splice_actor+0x80/0xa0 fs/splice.c:933
splice_direct_to_actor+0x345/0x650 fs/splice.c:888
do_splice_direct+0xf5/0x170 fs/splice.c:976
do_sendfile+0x5db/0xca0 fs/read_write.c:1257
__do_sys_sendfile64 fs/read_write.c:1312 [inline]
__se_sys_sendfile64 fs/read_write.c:1304 [inline]
__x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1304
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 25957 Comm: syz-executor.0 Not tainted 5.10.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.