[dm-devel] [PATCH] multipathd: avoid crash in uevent_cleanup()

[lixiaokeng]

> 
> I still don't fully understand. Above you said "this coredump doesn't
> seem to appear any more". Am I understanding correctly that you
> observed *other* core dumps instead?
> 

No, it is not "instead".
As shown in https://www.spinics.net/lists/dm-devel/msg45293.html,
there are some different crashes in multipathd with no code change.
When blocking of thread cancellation during udev_monitor_receive_device(),
no crash in udev_monitor_receive_device happens but others still
exist.

> 
> The "best" solution would probably be to generally disallow
> cancellation, and only run pthread_testcancel() at certain points in
> the code where we might block (and know that being cancelled would be
> safe). That would not only make multipathd safer from crashing, it
> would also enable us to remove hundreds of ugly
> pthread_cleanup_push()/pop() calls from our code.
> 
> Finding all these points would be a challenge though, and if we don't
> find them, we risk hanging on exit again, which is bad too, and was
> just recently improved.

Do you mean some patches have been made to solve these problem?

Regards,
Lixiaokeng