From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from Galois.linutronix.de ([146.0.238.70]:38871 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751154AbeACKgy (ORCPT ); Wed, 3 Jan 2018 05:36:54 -0500 Date: Wed, 3 Jan 2018 11:36:49 +0100 (CET) From: Thomas Gleixner To: Guillaume Tucker cc: Dave Hansen , Ingo Molnar , Greg Kroah-Hartman , kernel-build-reports@lists.linaro.org, Matt Hart , stable@vger.kernel.org, LKML , x86@kernel.org, Andy Lutomirski , Peter Zijlstra , Paolo Bonzini , qemu-devel@nongnu.org Subject: Re: stable/linux-4.14.y boot: 108 boots: 0 failed, 107 passed with 1 conflict (v4.14.11) In-Reply-To: Message-ID: References: <5a4c49c8.50b91c0a.2b051.322e@mx.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: stable-owner@vger.kernel.org List-ID: On Wed, 3 Jan 2018, Guillaume Tucker wrote: > On 03/01/18 09:48, Thomas Gleixner wrote: > > > Well, it turns out this is not exactly a conflict as there's a > > > subtle difference between the qemu devices in lab-mhart and in > > > lab-collabora. The ones in lab-collabora are configured to use > > > KVM, and it looks like the ones in lab-mhart aren't. > > > > > > So this job with KVM enabled passes in lab-collabora: > > > > > > https://lava.collabora.co.uk/scheduler/job/1032358 > > > > > > but it fails if I tell LAVA (qemu) to disable KVM: > > > > > > https://lava.collabora.co.uk/scheduler/job/1032359 > > > > > > with the same panic as in lab-mhart. It seems like it's failing > > > to return from an interrupt: > > > > > > http://lava.streamtester.net/scheduler/job/87308 > > > > > > [ 2.678828] ? native_iret+0x7/0x7 > > > [ 2.679208] WARNING: can't dereference iret registers at > > > 00000000ffc66068 > > > for ip page_fault+0x11/0x60 > > > > > > This triggered an automated bisection on kernelci.org, please see > > > the results below. > > > > > > I may run another bisection with this config enabled earlier in > > > the history to track down the actual change in the code that > > > introduced the issue, let me know if it's worth doing. > > > > No, because before that commit not all pieces are in place. > > > > Can you please try the failing kernel with pti=off on the command line? > > It does boot with pti=off (and KVM disabled): > > https://lava.collabora.co.uk/scheduler/job/1032387 So it's a qemu issue. Added qemu folks on Cc. > > I'll start a test instance here as well. Thanks, tglx