Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752030AbaBLKh0 (ORCPT ); Wed, 12 Feb 2014 05:37:26 -0500 Received: from merlin.infradead.org ([205.233.59.134]:32867 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751133AbaBLKhX (ORCPT ); Wed, 12 Feb 2014 05:37:23 -0500 Date: Wed, 12 Feb 2014 11:37:13 +0100 From: Peter Zijlstra To: Stefan Bader Cc: Paolo Bonzini , Linux Kernel Mailing List , kvm@vger.kernel.org, Marcelo Tosatti , MASAO TAKAHASHI , Joerg Roedel , Borislav Petkov Subject: Re: Another preempt folding issue? Message-ID: <20140212103713.GE3545@laptop.programming.kicks-ass.net> References: <52FA6D4B.7020709@canonical.com> <20140211194553.GZ9987@twins.programming.kicks-ass.net> <52FB2EC8.4080602@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52FB2EC8.4080602@canonical.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/