Re: CVS commit: src/sys/netinet

[Chuck Silvers <chuq%chuq.com@localhost>]

On Thu, Dec 28, 2017 at 05:34:27PM +0900, Ryota Ozaki wrote:
> On Thu, Dec 28, 2017 at 5:05 PM, Tom Ivar Helbekkmo
> <tih%hamartun.priv.no@localhost> wrote:
> > Ryota Ozaki <ozaki-r%NetBSD.org@localhost> writes:
> >
> >> I think the below patch fixes the above issue, but probably
> >> there is a better solution.
> >
> > Looks like didn't -- it just changed it a little bit.  Just like the
> > last time, the hang happened while reading email over IMAP, which
> > exercises disk and network at the same time, while the machine was busy
> > doing a parallellized system build in the background.  This time,
> > though, I got a core dump.  Here's the hang (the active process on this
> > CPU is the IMAP server):
> 
> Oh, my patch failed to keep SPL at IPL_VM because mutex_exit
> tries to restore an SPL where mutex_enter is called. So I had to
> put splvm before mutex_enter. Could you try the 2nd patch:
>   http://www.netbsd.org/~ozaki-r/fix-pool_catchup.diff

let's not mix explicit spl* calls with mutexes... even if that works
in this particular case, it doesn't seem like a good practice in general.
I was hoping to commit a different fix for this yesterday but I ran out of time.
I should have time this evening to get back to this.

-Chuck