On 2019/1/8 下午7:47, Peter Xu wrote:
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 <pet...@redhat.com>
---
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),
Acked-by: Jason Wang <jasow...@redhat.com>
