If pasid bits size is bigger than host side, host could fail to emulate all bindings in guest. Add a check to fail device plug early.
Signed-off-by: Zhenzhong Duan <[email protected]> --- hw/i386/intel_iommu_internal.h | 1 + hw/i386/intel_iommu_accel.c | 8 ++++++++ 2 files changed, 9 insertions(+) diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h index fe81c47819..2901cf44aa 100644 --- a/hw/i386/intel_iommu_internal.h +++ b/hw/i386/intel_iommu_internal.h @@ -194,6 +194,7 @@ #define VTD_ECAP_PRS (1ULL << 29) #define VTD_ECAP_MHMV (15ULL << 20) #define VTD_ECAP_SRS (1ULL << 31) +#define VTD_ECAP_PSS(x) extract64(x, 35, 5) #define VTD_ECAP_PASID (1ULL << 40) #define VTD_ECAP_SMTS (1ULL << 43) #define VTD_ECAP_SSTS (1ULL << 46) diff --git a/hw/i386/intel_iommu_accel.c b/hw/i386/intel_iommu_accel.c index a30786e361..61ff531803 100644 --- a/hw/i386/intel_iommu_accel.c +++ b/hw/i386/intel_iommu_accel.c @@ -44,6 +44,7 @@ bool vtd_check_hiod_accel(IntelIOMMUState *s, VTDHostIOMMUDevice *vtd_hiod, HostIOMMUDevice *hiod = vtd_hiod->hiod; struct HostIOMMUDeviceCaps *caps = &hiod->caps; struct iommu_hw_info_vtd *vtd = &caps->vendor_caps.vtd; + uint8_t hpasid = VTD_ECAP_PSS(vtd->ecap_reg) + 1; PCIBus *bus = vtd_hiod->bus; PCIDevice *pdev = bus->devices[vtd_hiod->devfn]; @@ -64,6 +65,13 @@ bool vtd_check_hiod_accel(IntelIOMMUState *s, VTDHostIOMMUDevice *vtd_hiod, return false; } + /* Only do the check when host device support PASIDs */ + if (caps->max_pasid_log2 && s->pasid > hpasid) { + error_setg(errp, "PASID bits size %d > host IOMMU PASID bits size %d", + s->pasid, hpasid); + return false; + } + if (pci_device_get_iommu_bus_devfn(pdev, &bus, NULL, NULL)) { error_setg(errp, "Host device downstream to a PCI bridge is " "unsupported when x-flts=on"); -- 2.47.3
