From e6e62ad1e8a33076b67b19ce5f03ea6ca6571eef Mon Sep 17 00:00:00 2001
From: Eduardo Habkost <ehabkost@redhat.com>
Date: Thu, 9 May 2019 22:43:17 +0100
Subject: [PATCH 1/2] kvm: Use KVM_GET_MSR_INDEX_LIST for
 MSR_IA32_ARCH_CAPABILITIES support

RH-Author: Eduardo Habkost <ehabkost@redhat.com>
Message-id: <20190509224318.23376-2-ehabkost@redhat.com>
Patchwork-id: 87251
O-Subject: [RHEL-8.1.0 qemu-kvm PATCH 1/2] kvm: Use KVM_GET_MSR_INDEX_LIST for MSR_IA32_ARCH_CAPABILITIES support
Bugzilla: 1707706
RH-Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>
RH-Acked-by: Igor Mammedov <imammedo@redhat.com>
RH-Acked-by: Bandan Das <bsd@redhat.com>

From: Bandan Das <bsd@redhat.com>

When writing to guest's MSR_IA32_ARCH_CAPABILITIES, check whether it's
supported in the guest using the KVM_GET_MSR_INDEX_LIST ioctl.

Fixes: d86f963694df27f11b3681ffd225c9362de1b634
Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Tested-by: balducci@units.it
Signed-off-by: Bandan Das <bsd@redhat.com>
Message-Id: <jpg4lc4iiav.fsf_-_@linux.bootlegged.copy>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
(cherry picked from commit aec5e9c3a94cf8b7920f59bef69a6f426092c4a0)
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
 target/i386/kvm.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index f1626a4..e3e8c78 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -94,6 +94,7 @@ static bool has_msr_xss;
 static bool has_msr_spec_ctrl;
 static bool has_msr_virt_ssbd;
 static bool has_msr_smi_count;
+static bool has_msr_arch_capabs;
 
 static uint32_t has_architectural_pmu_version;
 static uint32_t num_architectural_pmu_gp_counters;
@@ -1330,6 +1331,9 @@ static int kvm_get_supported_msrs(KVMState *s)
                 case MSR_VIRT_SSBD:
                     has_msr_virt_ssbd = true;
                     break;
+                case MSR_IA32_ARCH_CAPABILITIES:
+                    has_msr_arch_capabs = true;
+                    break;
                 }
             }
         }
@@ -1834,14 +1838,9 @@ static int kvm_put_msrs(X86CPU *cpu, int level)
 #endif
 
     /* If host supports feature MSR, write down. */
-    if (kvm_feature_msrs) {
-        int i;
-        for (i = 0; i < kvm_feature_msrs->nmsrs; i++)
-            if (kvm_feature_msrs->indices[i] == MSR_IA32_ARCH_CAPABILITIES) {
-                kvm_msr_entry_add(cpu, MSR_IA32_ARCH_CAPABILITIES,
-                              env->features[FEAT_ARCH_CAPABILITIES]);
-                break;
-            }
+    if (has_msr_arch_capabs) {
+        kvm_msr_entry_add(cpu, MSR_IA32_ARCH_CAPABILITIES,
+                          env->features[FEAT_ARCH_CAPABILITIES]);
     }
 
     /*
-- 
1.8.3.1