KCSAN: data-race in __mark_inode_dirty / writeback_sb_inodes (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 23859ae4 Merge tag 'trace-v5.10-rc1' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1263767c500000
kernel config: https://syzkaller.appspot.com/x/.config?x=2cd30dd5bfd84384
dashboard link: https://syzkaller.appspot.com/bug?extid=d98998b6cacef9fecc92
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]

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+d98998...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __mark_inode_dirty / writeback_sb_inodes

write to 0xffff88810d70c398 of 8 bytes by task 26 on cpu 1:
writeback_sb_inodes+0x494/0x1020 fs/fs-writeback.c:1710
wb_writeback+0x27d/0x660 fs/fs-writeback.c:1894
wb_do_writeback+0x101/0x5d0 fs/fs-writeback.c:2039
wb_workfn+0xb8/0x410 fs/fs-writeback.c:2080
process_one_work+0x3e1/0x950 kernel/workqueue.c:2272
worker_thread+0x635/0xb90 kernel/workqueue.c:2418
kthread+0x1fa/0x220 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

read to 0xffff88810d70c398 of 8 bytes by task 26432 on cpu 0:
__mark_inode_dirty+0xb7/0x740 fs/fs-writeback.c:2274
mark_buffer_dirty+0x143/0x230 fs/buffer.c:1141
__block_commit_write fs/buffer.c:2084 [inline]
block_write_end+0x13d/0x230 fs/buffer.c:2162
generic_write_end+0x5b/0x250 fs/buffer.c:2176
ext4_da_write_end+0x59b/0x760 fs/ext4/inode.c:3100
generic_perform_write+0x23e/0x3a0 mm/filemap.c:3322
ext4_buffered_write_iter+0x2e5/0x3d0 fs/ext4/file.c:270
ext4_file_write_iter+0x45e/0x1090 fs/ext4/file.c:503
call_write_iter include/linux/fs.h:1887 [inline]
new_sync_write fs/read_write.c:518 [inline]
vfs_write+0x617/0x690 fs/read_write.c:605
ksys_write+0xce/0x180 fs/read_write.c:658
__do_sys_write fs/read_write.c:670 [inline]
__se_sys_write fs/read_write.c:667 [inline]
__x64_sys_write+0x3e/0x50 fs/read_write.c:667
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: 0 PID: 26432 Comm: syz-executor.1 Not tainted 5.10.0-rc1-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.