On Wed, Feb 1, 2023 at 4:46 AM Xiao Ni [off-list ref] wrote:

It has added io_acct_set for raid0/raid5 io accounting and it needs to
alloc md_io_acct in the i/o path. They are free when the bios come back
from member disks. Now we don't have a method to monitor if those bios
are all come back. In the takeover process, it needs to free the raid0
memory resource including the memory pool for md_io_acct. But maybe some
bios are still not returned. When those bios are returned, it can cause
panic bcause of introducing NULL pointer or invalid address. Something
like this:

Can we use mddev->active_io for this? If not, please explain the reason
in the comments (in the code).

[...]

+       } else

Please add { } for the else clause.

Thanks,
Song

+               if (percpu_ref_is_dying(&mddev->io_acct_cnt))
+                       percpu_ref_resurrect(&mddev->io_acct_cnt);
 }

 static struct md_personality raid0_personality=
--
2.32.0 (Apple Git-132)