On 9/16/24 10:31, Santosh Shukla wrote:
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");
Use "xtsup=on" on the error message, "xt" is not a valid option IIUC.
Alejandro
+ exit(EXIT_FAILURE);
+ }
+
pci_setup_iommu(bus, &amdvi_iommu_ops, s);
amdvi_init(s);
}
