From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51076) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b0O1Q-00075R-Sx for qemu-devel@nongnu.org; Wed, 11 May 2016 02:53:30 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1b0O1L-0008Fb-MS for qemu-devel@nongnu.org; Wed, 11 May 2016 02:53:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48558) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b0O1L-0008FX-Gc for qemu-devel@nongnu.org; Wed, 11 May 2016 02:53:23 -0400 Date: Wed, 11 May 2016 14:53:18 +0800 From: Peter Xu Message-ID: <20160511065318.GA13293@pxdev.xzpeter.org> References: <1462948831-931-1-git-send-email-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1462948831-931-1-git-send-email-peterx@redhat.com> Subject: Re: [Qemu-devel] [PATCH] pci: fix requester id with PCI bridges List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: rkrcmar@redhat.com, mst@redhat.com, alex.williamson@redhat.com, jan.kiszka@web.de, pbonzini@redhat.com On Wed, May 11, 2016 at 02:40:30PM +0800, Peter Xu wrote: > Recently I encountered issue when debugging Intel IOMMU IR codes, > that interrupts are not working correctly with PCI bridges (reported > by Radim). This patch fixes the problem. I assume requester ID > should be the devfn on root PCI bus (that's how I understand it > before, and also in guest kernel, IRTE entry SID is filled in that > way), however I failed to find any good document to confirm > this. Please let me know if this is correct (or I made any > mistake). One thing to mention is that, this patch does *not* fix the problem if directly applied, because IR patchset introduced another patch that also need a similar fix. In case if there is someone (Radim?) who would like to try this patch, we need to apply this patch as well: ---8<--- diff --git a/target-i386/kvm.c b/target-i386/kvm.c index 80b3251..0876a1c 100644 --- a/target-i386/kvm.c +++ b/target-i386/kvm.c @@ -3342,7 +3342,8 @@ int kvm_arch_fixup_msi_route(struct kvm_irq_routing_entry *route, src.data = route->u.msi.data; ret = class->int_remap(iommu, &src, &dst, dev ? \ - pci_requester_id(dev) : X86_IOMMU_SID_INVALID); + pci_requester_id_recursive(dev) : \ + X86_IOMMU_SID_INVALID); if (ret) { trace_kvm_x86_fixup_msi_error(route->gsi); return 1; --->8--- This should be able to be applied directly onto IR v6 patchset as well. Thanks, -- peterx