Re: [PATCH v3 for-5.1 0/2] Fix crash due to NBD export leak

[Kevin Wolf]

Am 14.07.2020 um 18:22 hat Vladimir Sementsov-Ogievskiy geschrieben:
> Hi all!
> 
> We've faced crash bug, which is reproducing on master branch as well.
> The case is described in 01, where fix is suggested.
> New iotest in 02 crashes without that fix.
> 
> v3: resend for convenience, as all preparatory patches are merged.
> 01-02: add Eric's r-b and t-b marks
> 
> ====
> 
> This is a crash-fix, so it would be good to fix in 5.1. Still neither
> Eric nor I are sure in patch 01: is AIO_WAIT_WHILE used correctly?

Anything specific you had doubts about?

At first sight it looks good to me. It's always called in the main loop
and we don't hold any AioContext locks, so using NULL as the context is
fine. You also made sure to use aio_wait_kick() so that we won't hang
even though the condition has become false.

I'm applying this to my block branch now. If your doubts were about
something more subtle that I missed, we can unstage/revert the patch.

Kevin