From: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com> The XTSup mode enables x2APIC support for AMD IOMMU, which is needed to support vcpu w/ APIC ID > 255.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com> Signed-off-by: Santosh Shukla <santosh.shu...@amd.com> --- v2: - Fixed non-kvm build issue by adding a check for kvm_irqchip_is_split() hw/i386/amd_iommu.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c index 9095146525e6..24eebf053df0 100644 --- a/hw/i386/amd_iommu.c +++ b/hw/i386/amd_iommu.c @@ -32,6 +32,7 @@ #include "trace.h" #include "hw/i386/apic-msidef.h" #include "hw/qdev-properties.h" +#include "kvm/kvm_i386.h" /* used AMD-Vi MMIO registers */ const char *amdvi_mmio_low[] = { @@ -1651,6 +1652,16 @@ static void amdvi_sysbus_realize(DeviceState *dev, Error **errp) memory_region_add_subregion_overlap(&s->mr_sys, AMDVI_INT_ADDR_FIRST, &s->mr_ir, 1); + /* AMD IOMMU with x2APIC mode requires xtsup=on */ + if (x86ms->apic_id_limit > 255 && !s->xtsup) { + error_report("AMD IOMMU with x2APIC confguration requires xtsup=on"); + exit(EXIT_FAILURE); + } + if (s->xtsup && kvm_irqchip_is_split() && !kvm_enable_x2apic()) { + error_report("AMD IOMMU xt=on requires support on the KVM side"); + exit(EXIT_FAILURE); + } + pci_setup_iommu(bus, &amdvi_iommu_ops, s); amdvi_init(s); } -- 2.43.5