From patchwork Tue Oct 23 23:41:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 988407 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 42fqpg2yp5z9s3Z for ; Wed, 24 Oct 2018 10:48:43 +1100 (AEDT) Received: from localhost ([::1]:44759 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gF6Ph-0000qr-0Z for incoming@patchwork.ozlabs.org; Tue, 23 Oct 2018 19:48:41 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51355) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gF6JC-0003Bc-P7 for qemu-devel@nongnu.org; Tue, 23 Oct 2018 19:42:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gF6JA-000854-QW for qemu-devel@nongnu.org; Tue, 23 Oct 2018 19:41:58 -0400 Received: from [185.30.24.106] (port=13368 helo=hotspot.internet-for-guests.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gF6J6-0007h2-BG for qemu-devel@nongnu.org; Tue, 23 Oct 2018 19:41:53 -0400 Received: from redhat.com (unknown [172.29.18.113]) by hotspot.internet-for-guests.com (Postfix) with SMTP id 409F66402ED; Wed, 24 Oct 2018 00:41:30 +0100 (BST) Date: Tue, 23 Oct 2018 19:41:31 -0400 From: "Michael S. Tsirkin" To: qemu-devel@nongnu.org Message-ID: <20181023234112.188140-6-mst@redhat.com> References: <20181023234112.188140-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20181023234112.188140-1-mst@redhat.com> X-Mailer: git-send-email 2.17.1.1206.gb667731e2e.dirty X-Mutt-Fcc: =sent X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 185.30.24.106 Subject: [Qemu-devel] [PULL 05/28] intel_iommu: handle invalid ce for shadow sync X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Eduardo Habkost , Peter Xu , Eric Auger , Maxime Coquelin , Pei Zhang , Paolo Bonzini , Richard Henderson Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Peter Xu We should handle VTD_FR_CONTEXT_ENTRY_P properly when synchronizing shadow page tables. Having invalid context entry there is perfectly valid when we move a device out of an existing domain. When that happens, instead of posting an error we invalidate the whole region. Without this patch, QEMU will crash if we do these steps: (1) start QEMU with VT-d IOMMU and two 10G NICs (ixgbe) (2) bind the NICs with vfio-pci in the guest (3) start testpmd with the NICs applied (4) stop testpmd (5) rebind the NIC back to ixgbe kernel driver The patch should fix it. Reported-by: Pei Zhang Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1627272 Signed-off-by: Peter Xu Reviewed-by: Eric Auger Reviewed-by: Maxime Coquelin Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/i386/intel_iommu.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index 25e54671f4..f24ebfca1c 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -38,6 +38,7 @@ #include "trace.h" static void vtd_address_space_refresh_all(IntelIOMMUState *s); +static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n); static void vtd_define_quad(IntelIOMMUState *s, hwaddr addr, uint64_t val, uint64_t wmask, uint64_t w1cmask) @@ -1066,11 +1067,27 @@ static int vtd_sync_shadow_page_table(VTDAddressSpace *vtd_as) { int ret; VTDContextEntry ce; + IOMMUNotifier *n; ret = vtd_dev_to_context_entry(vtd_as->iommu_state, pci_bus_num(vtd_as->bus), vtd_as->devfn, &ce); if (ret) { + if (ret == -VTD_FR_CONTEXT_ENTRY_P) { + /* + * It's a valid scenario to have a context entry that is + * not present. For example, when a device is removed + * from an existing domain then the context entry will be + * zeroed by the guest before it was put into another + * domain. When this happens, instead of synchronizing + * the shadow pages we should invalidate all existing + * mappings and notify the backends. + */ + IOMMU_NOTIFIER_FOREACH(n, &vtd_as->iommu) { + vtd_address_space_unmap(vtd_as, n); + } + ret = 0; + } return ret; }