linux-kernel - Re: Another preempt folding issue?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20140212103713.GE3545@laptop.programming.kicks-ass.net>
Date:	Wed, 12 Feb 2014 11:37:13 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Stefan Bader <stefan.bader@...onical.com>
Cc:	Paolo Bonzini <pbonzini@...hat.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	kvm@...r.kernel.org, Marcelo Tosatti <mtosatti@...hat.com>,
	MASAO TAKAHASHI <masao-takahashi@...no.co.jp>,
	Joerg Roedel <joro@...tes.org>, Borislav Petkov <bp@...en8.de>
Subject: Re: Another preempt folding issue?

On Wed, Feb 12, 2014 at 09:20:24AM +0100, Stefan Bader wrote:
> On 11.02.2014 20:45, Peter Zijlstra wrote:
> > On Tue, Feb 11, 2014 at 07:34:51PM +0100, Stefan Bader wrote:
> >> Hi Peter,
> >>
> >> I am currently looking at a weird issue that manifest itself when trying to run
> >> kvm enabled qemu on a i386 host (v3.13 kernel, oh and potentially important the
> >> cpu is 64bit capable, so qemu-system-x86_64 is called). 
> > 
> > AMD or Intel machine?
> 
> Personally I am reproducing this on an AMD:
> 
> cpu family	: 15
> model		: 72
> model name	: AMD Turion(tm) 64 X2 Mobile Technology TL-64
> 
> but the reports I got are showing the same issue on an Intel i7
> 
> cpu family	: 6
> model		: 37
> model name	: Intel(R) Core(TM) i7 CPU       M 620  @ 2.67GH
> 
> Another reporter also saw this on an AMD and said it could not be reproduced on
> the same hardware and the same software versions when using 64bit instead of 32.
> 
> In my case on a 32bit installation I will see this on every invocation of

Curious.. so its both AMD and Intel.

That makes funny hardware less likely... but how can the vmexit loose an
interrupt like this.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/