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Message-ID: <1504001022.8323.24.camel@gmx.de>
Subject: Re: tip -ENOBOOT - bisected to locking/refcounts, x86/asm:
 Implement fast refcount overflow protection
From: Mike Galbraith <efault@gmx.de>
To: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>, LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@elte.hu>, Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Elena Reshetova <elena.reshetova@intel.com>,
        Arnd Bergmann <arnd@arndb.de>, "H. Peter Anvin" <hpa@zytor.com>
Date: Tue, 29 Aug 2017 12:03:42 +0200
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On Tue, 2017-08-29 at 11:27 +0200, Ingo Molnar wrote:
> * Mike Galbraith <efault@gmx.de> wrote:
> 
> > On Tue, 2017-08-29 at 10:58 +0200, Ingo Molnar wrote:
> > > * Mike Galbraith <efault@gmx.de> wrote:
> > > 
> > > > Greetings,
> > > > 
> > > > Take 2 of KVM bisect as you work fingered $subject.  Take 1 was stymied
> > > > by build dependencies (aa5d1b81, df340524) which I foolishly tried to
> > > > skip, leading git bisect to end up handing me a list of commits that
> > > > might be busted.  During take 2, I added those two as required.
> > > > 
> > > > Symptom is a few splats as below, with box finally hanging.  Network
> > > > comes up, but neither ssh nor console login is possible.
> > > 
> > > Just to double check, does the patch below also cure the regression?
> > > If we don't find the bug it might be safer than a full revert.
> > 
> > I reverted it, and vbox now boots.  Should I still try the below?
> 
> Would be nice, so I can stick a Tested-by on it and such!

Done, works.

	-Mike