Message-ID: <1462055616.10011.62.camel@poochiereds.net>
Subject: Re: parallel lookups on NFS
From: Jeff Layton <jlayton@poochiereds.net>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Trond Myklebust <trond.myklebust@primarydata.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Anna Schumaker <Anna.Schumaker@netapp.com>
Date: Sat, 30 Apr 2016 18:33:36 -0400
In-Reply-To: <20160430205705.GE25498@ZenIV.linux.org.uk>
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On Sat, 2016-04-30 at 21:57 +0100, Al Viro wrote:
> On Sat, Apr 30, 2016 at 04:39:25PM -0400, Jeff Layton wrote:
> 
> > 
> > Attached. Also I ran the same test on a 4.6.0-rc1 kernel and it
> > worked
> > fine, so it does seem to be a regression introduced somewhere in
> > your
> > patch pile. Also, FWIW the machine is a KVM guest.
> OK...  Could you try #work.lookups on your setup?  That doesn't
> contain the
> last commit; the deadlock ought to be dealt with, though.  I'm trying
> to
> reproduce the corruption with KASAN enabled, will try your config
> once that's
> finished...

I'll do the same (re: KASAN).

Also FWIW, a few months ago I hit some oopses in the same inline
function (get_freepointer). It turned out to be a double-free due to my
own misuse of the fsnotify API. I wonder though if this might also be a
double free somewhere?

-- 
Jeff Layton <jlayton@poochiereds.net>