From 0004d2f3b0c3b21336415a967d70b7e9c2d08f54 Mon Sep 17 00:00:00 2001
Message-Id: <0004d2f3b0c3b21336415a967d70b7e9c2d08f54@dist-git>
From: Jiri Denemark <jdenemar@redhat.com>
Date: Fri, 21 Jun 2019 09:26:09 +0200
Subject: [PATCH] cpu_x86: Read CPU features from IA32_ARCH_CAPABILITIES MSR
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This is used by the host capabilities code to construct host CPU
definition.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
(cherry picked from commit 56b254dccc96b7339494812c9df07ccf6af3da95)
https://bugzilla.redhat.com/show_bug.cgi?id=1697627
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Message-Id: <58ad207c48e0f2a6c44ff097b0881b649826ecd4.1561068591.git.jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
---
src/cpu/cpu_x86.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/src/cpu/cpu_x86.c b/src/cpu/cpu_x86.c
index ec0e408f98..0a520f07ff 100644
--- a/src/cpu/cpu_x86.c
+++ b/src/cpu/cpu_x86.c
@@ -2771,6 +2771,28 @@ 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
+ * when we are not running as root. */
+ if (virCPUx86DataCheckFeature(cpuData, "arch-capabilities") == 1) {
+ uint64_t msr;
+ unsigned long index = 0x10a;
+
+ if (virHostCPUGetMSR(index, &msr) == 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();
--
2.22.0