From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: 2.6.38.1 general protection fault
Date: Tue, 29 Mar 2011 10:34:38 -0300
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Cc: Tomasz Chmielewski <mangoo@wpkg.org>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	Andrea Arcangeli <aarcange@redhat.com>
To: Avi Kivity <avi@redhat.com>
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On Mon, Mar 28, 2011 at 11:19:51AM +0200, Avi Kivity wrote:
> On 03/28/2011 08:24 AM, Tomasz Chmielewski wrote:
> >On 27.03.2011 11:42, Avi Kivity wrote:
> >
> >(...)
> >
> >>Okay, the fork came from the ,script=.
> >>
> >>The issue with %rsi looks like a use-after-free, however
> >>kvm_mmu_notifier_invalidate_range_start appears to be properly srcu
> >>protected.
> >
> >FYI, I saw this one as well:
> >
> >http://www.virtall.com/files/temp/kvm.txt
> 
> Similar pattern - top 16 bits of %rsi are flipped.
> 
> Marcelo, what was the option to enable padding for allocations and
> overrun detection?  Also use-after-free?

slub_debug=ZFPU boot kernel parameter.

Documentation/vm/slub.txt:

Possible debug options are
        F               Sanity checks on (enables SLAB_DEBUG_FREE. Sorry
                        SLAB legacy issues)
        Z               Red zoning
        P               Poisoning (object and padding)
        U               User tracking (free and alloc)