[libvirt] [PATCH 35/36] cpu_x86: Read CPU features from IA32_ARCH_CAPABILITIES MSR
This is used by the host capabilities code to construct host CPU
definition.
Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com>
---
src/cpu/cpu_x86.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/src/cpu/cpu_x86.c b/src/cpu/cpu_x86.c
index 1fe6770d57..74385f7992 100644
--- a/src/cpu/cpu_x86.c
+++ b/src/cpu/cpu_x86.c
@@ -2759,6 +2759,30 @@ virCPUx86GetHost(virCPUDefPtr cpu,
cpuidSet(CPUX86_EXTENDED, cpuData) < 0)
goto cleanup;
+ /* Read the IA32_ARCH_CAPABILITIES MSR (0x10a) if supported.
+ * This is best effort since there might be no way to read the MSR. */
+ if (virCPUx86DataCheckFeature(cpuData, "arch-capabilities") == 1) {
+ uint64_t msr;
+ unsigned long index = 0x10a;
+ int rc = virHostCPUGetMSR(index, &msr);
+
+ if (rc < 0) {
+ virResetLastError();
+ } else if (rc == 0) {
+ virCPUx86DataItem item = {
+ .type = VIR_CPU_X86_DATA_MSR,
+ .data.msr = {
+ .index = index,
+ .eax = msr & 0xffffffff,
+ .edx = msr >> 32,
+ },
+ };
+
+ if (virCPUx86DataAdd(cpuData, &item) < 0)
+ return -1;
+ }
+ }
+
ret = x86DecodeCPUData(cpu, cpuData, models);
cpu->microcodeVersion = virHostCPUGetMicrocodeVersion();
--
2.21.0