[PATCH v5 04/11] target/i386/kvm: Only save/load kvmclock MSRs when kvmclock enabled

Zhao Liu posted 11 patches 2 weeks, 3 days ago
[PATCH v5 04/11] target/i386/kvm: Only save/load kvmclock MSRs when kvmclock enabled
Posted by Zhao Liu 2 weeks, 3 days ago
MSR_KVM_SYSTEM_TIME and MSR_KVM_WALL_CLOCK are attached with the (old)
kvmclock feature (KVM_FEATURE_CLOCKSOURCE).

So, just save/load them only when kvmclock (KVM_FEATURE_CLOCKSOURCE) is
enabled.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Zide Chen <zide.chen@intel.com>
---
 target/i386/kvm/kvm.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 54520a77d6af..4aba034865bb 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -3958,8 +3958,10 @@ static int kvm_put_msrs(X86CPU *cpu, int level)
      */
     if (level >= KVM_PUT_RESET_STATE) {
         kvm_msr_entry_add(cpu, MSR_IA32_TSC, env->tsc);
-        kvm_msr_entry_add(cpu, MSR_KVM_SYSTEM_TIME, env->system_time_msr);
-        kvm_msr_entry_add(cpu, MSR_KVM_WALL_CLOCK, env->wall_clock_msr);
+        if (env->features[FEAT_KVM] & CPUID_KVM_CLOCK) {
+            kvm_msr_entry_add(cpu, MSR_KVM_SYSTEM_TIME, env->system_time_msr);
+            kvm_msr_entry_add(cpu, MSR_KVM_WALL_CLOCK, env->wall_clock_msr);
+        }
         if (env->features[FEAT_KVM] & CPUID_KVM_ASYNCPF_INT) {
             kvm_msr_entry_add(cpu, MSR_KVM_ASYNC_PF_INT, env->async_pf_int_msr);
         }
@@ -4436,8 +4438,10 @@ static int kvm_get_msrs(X86CPU *cpu)
         }
     }
 #endif
-    kvm_msr_entry_add(cpu, MSR_KVM_SYSTEM_TIME, 0);
-    kvm_msr_entry_add(cpu, MSR_KVM_WALL_CLOCK, 0);
+    if (env->features[FEAT_KVM] & CPUID_KVM_CLOCK) {
+        kvm_msr_entry_add(cpu, MSR_KVM_SYSTEM_TIME, 0);
+        kvm_msr_entry_add(cpu, MSR_KVM_WALL_CLOCK, 0);
+    }
     if (env->features[FEAT_KVM] & CPUID_KVM_ASYNCPF_INT) {
         kvm_msr_entry_add(cpu, MSR_KVM_ASYNC_PF_INT, 0);
     }
-- 
2.34.1