From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:37927) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ggprY-0007au-T5 for qemu-devel@nongnu.org; Tue, 08 Jan 2019 06:48:07 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ggprN-0003RN-UA for qemu-devel@nongnu.org; Tue, 08 Jan 2019 06:48:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:48882) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ggprN-0003Pc-Mi for qemu-devel@nongnu.org; Tue, 08 Jan 2019 06:47:53 -0500 From: Peter Xu Date: Tue, 8 Jan 2019 19:47:16 +0800 Message-Id: <20190108114720.21760-2-peterx@redhat.com> In-Reply-To: <20190108114720.21760-1-peterx@redhat.com> References: <20190108114720.21760-1-peterx@redhat.com> Subject: [Qemu-devel] [PATCH 1/5] intel_iommu: fix operator in vtd_switch_address_space List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: "Michael S . Tsirkin" , Paolo Bonzini , Marcel Apfelbaum , Alex Williamson , Eric Auger , peterx@redhat.com, Jason Wang When calculating use_iommu, we wanted to first detect whether DMAR is enabled, then check whether PT is enabled if DMAR is enabled. However in the current code we used "&" rather than "&&" so the ordering requirement is lost (instead it'll be an "AND" operation). This could introduce errors dumped in QEMU console when rebooting a guest with both assigned device and vIOMMU, like: qemu-system-x86_64: vtd_dev_to_context_entry: invalid root entry: rsvd=0xf000ff53f000e2c3, val=0xf000ff53f000ff53 (reserved nonzero) Signed-off-by: Peter Xu --- hw/i386/intel_iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index 8b72735650..6d5cc1d039 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -1153,7 +1153,7 @@ static bool vtd_switch_address_space(VTDAddressSpace *as) assert(as); - use_iommu = as->iommu_state->dmar_enabled & !vtd_dev_pt_enabled(as); + use_iommu = as->iommu_state->dmar_enabled && !vtd_dev_pt_enabled(as); trace_vtd_switch_address_space(pci_bus_num(as->bus), VTD_PCI_SLOT(as->devfn), -- 2.17.1