Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756208AbcDMB24 (ORCPT ); Tue, 12 Apr 2016 21:28:56 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:48079 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751648AbcDMB2y (ORCPT ); Tue, 12 Apr 2016 21:28:54 -0400 Subject: Re: Xen regression, Was: [PATCH] x86/irq: Probe for PIC presence before allocating descs for legacy IRQs To: Stefano Stabellini References: <1446470676-1877-1-git-send-email-vkuznets@redhat.com> <570CF69A.1020701@oracle.com> <570D4645.20004@oracle.com> <570D69FE.6090200@oracle.com> <570D77D1.7080701@oracle.com> Cc: Vitaly Kuznetsov , x86@kernel.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Jiang Liu , "K. Y. Srinivasan" , linux-kernel@vger.kernel.org, konrad.wilk@oracle.com, david.vrabel@citrix.com, jgross@suse.com From: Boris Ostrovsky Message-ID: <570DA089.6060507@oracle.com> Date: Tue, 12 Apr 2016 21:27:37 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Source-IP: userv0022.oracle.com [156.151.31.74] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 813 Lines: 20 On 04/12/2016 07:15 PM, Stefano Stabellini wrote: > On Tue, 12 Apr 2016, Boris Ostrovsky wrote: >> On 04/12/2016 05:56 PM, Stefano Stabellini wrote: >>> I am not sure, maybe you didn't have CONFIG_SPARSE_IRQ? >>> But I am certain that 4.6-rc2, with the attached config, fails as Dom0 >>> on QEMU with the following sequence of calls: >> I did have CONFIG_SPARSE_IRQ and I just rebuilt 4.5.0 with your config >> (4.6-rc3 doesn't build for me for some reason) and that booted dom0 as well. >> >> BTW, what do you mean by "dom0 on QEMU"? > > I am running Xen and Linux inside a QEMU x86_64 emulated machine (nested > virt). This I, of course, never tried. But given that things work in a single-level virt, doesn't this imply that perhaps there is something in the emulation that's not quite right? -boris