From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752370AbbJTMLu (ORCPT ); Tue, 20 Oct 2015 08:11:50 -0400 Received: from mail-wi0-f171.google.com ([209.85.212.171]:38178 "EHLO mail-wi0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751212AbbJTMLr (ORCPT ); Tue, 20 Oct 2015 08:11:47 -0400 Subject: Re: [Xen-devel] PROBLEM: kernel panic xsave_init To: Jan Beulich , Boris Ostrovsky References: <562430E6.6010205@gmail.com> <20151019075618.GA22488@gmail.com> <5624C2FB.6080605@gmail.com> <56251973.9010603@oracle.com> <56262AD802000078000ACAA1@prv-mh.provo.novell.com> Cc: Ingo Molnar , x86@kernel.org, xen-devel@lists.xen.org, linux-kernel@vger.kernel.org From: John Doe X-Enigmail-Draft-Status: N1110 Message-ID: <56262F81.804@gmail.com> Date: Tue, 20 Oct 2015 14:11:45 +0200 MIME-Version: 1.0 In-Reply-To: <56262AD802000078000ACAA1@prv-mh.provo.novell.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/10/2015 11:51, Jan Beulich wrote: >>>> On 19.10.15 at 18:25, wrote: >> On 10/19/2015 06:16 AM, John Doe wrote: >>>>> [ 0.000000] general protection fault: 0000 [#1] SMP >>>>> [ 0.000000] Modules linked in: >>>>> [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted >> 4.1.9-6.pvops.qubes.x86_64 #1 >>>>> [ 0.000000] Hardware name: To Be Filled By O.E.M. To Be Filled By >> O.E.M./Z170 Extreme4, BIOS P1.80 09/18/2015 >>>>> [ 0.000000] task: ffffffff81c154c0 ti: ffffffff81c00000 task.ti: >> ffffffff81c00000 >>>>> [ 0.000000] RIP: e030:[] [] >> xstate_enable_boot_cpu+0xde/0x288 >>>>> [ 0.000000] RSP: e02b:ffffffff81c03de8 EFLAGS: 00010046 >>>>> [ 0.000000] RAX: 000000000000001f RBX: 0000000000000008 RCX: >> 0000000000000000 >>>>> [ 0.000000] RDX: 0000000000000000 RSI: 000000000000001f RDI: >> 0000000000042660 >> >> >> It would be good to see what's at ffffffff81d58fad. My guess would be >> that it's xsetbv. >> >> If it is then you probably want to make sure you are running hypervisor >> that has commit e8121c54 ("x86/xsave: enable support for new ISA >> extensions"). Looks like the first version that has it is 4.5 and you >> seem to be running 4.4.2. >> >> Copying Jan to see if there are plans to backport this (probably not >> since it's a new feature). > > Hmm, if there are features getting exposed that lead to crashes like > this, then while we wouldn't normally backport enhancements, we > may need to consider adding a one-off patch to hide respective > features to that stable branch. But first we of course need to > understand what is going on here. > > Jan > I will try with 4.6.0 asap, unfortunately the 4.4.2 image i have is not built with debug enabled and i'm unable to run gdb at boot, i'm building a new one right now. If you need anything else please be very step-specific since i'm not very practical at this. Thank you, John.