Patchwork [31/31] kvm: x86: Only read/write MSR_KVM_ASYNC_PF_EN if supported

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Submitter Marcelo Tosatti
Date Jan. 24, 2011, 9:02 a.m.
Message ID <c5999bfcfdf66390c98115044cb6fd174fbcf36d.1295859760.git.mtosatti@redhat.com>
Download mbox | patch
Permalink /patch/80105/
State New
Headers show

Comments

Marcelo Tosatti - Jan. 24, 2011, 9:02 a.m.
From: Jan Kiszka <jan.kiszka@siemens.com>

If the kernel does not support KVM_CAP_ASYNC_PF, it also does not know
about the related MSR. So skip it during state synchronization in that
case. Fixes annoying kernel warnings.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
---
 target-i386/kvm.c |   13 +++++++++++--
 1 files changed, 11 insertions(+), 2 deletions(-)

Patch

diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index b2c5ee0..8e8880a 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -63,6 +63,9 @@  const KVMCapabilityInfo kvm_arch_required_capabilities[] = {
 
 static bool has_msr_star;
 static bool has_msr_hsave_pa;
+#if defined(CONFIG_KVM_PARA) && defined(KVM_CAP_ASYNC_PF)
+static bool has_msr_async_pf_en;
+#endif
 static int lm_capable_kernel;
 
 static struct kvm_cpuid2 *try_get_cpuid(KVMState *s, int max)
@@ -164,6 +167,7 @@  static int get_para_features(CPUState *env)
             features |= (1 << para_features[i].feature);
         }
     }
+    has_msr_async_pf_en = features & (1 << KVM_FEATURE_ASYNC_PF);
     return features;
 }
 #endif
@@ -828,7 +832,10 @@  static int kvm_put_msrs(CPUState *env, int level)
                           env->system_time_msr);
         kvm_msr_entry_set(&msrs[n++], MSR_KVM_WALL_CLOCK, env->wall_clock_msr);
 #if defined(CONFIG_KVM_PARA) && defined(KVM_CAP_ASYNC_PF)
-        kvm_msr_entry_set(&msrs[n++], MSR_KVM_ASYNC_PF_EN, env->async_pf_en_msr);
+        if (has_msr_async_pf_en) {
+            kvm_msr_entry_set(&msrs[n++], MSR_KVM_ASYNC_PF_EN,
+                              env->async_pf_en_msr);
+        }
 #endif
     }
 #ifdef KVM_CAP_MCE
@@ -1064,7 +1071,9 @@  static int kvm_get_msrs(CPUState *env)
     msrs[n++].index = MSR_KVM_SYSTEM_TIME;
     msrs[n++].index = MSR_KVM_WALL_CLOCK;
 #if defined(CONFIG_KVM_PARA) && defined(KVM_CAP_ASYNC_PF)
-    msrs[n++].index = MSR_KVM_ASYNC_PF_EN;
+    if (has_msr_async_pf_en) {
+        msrs[n++].index = MSR_KVM_ASYNC_PF_EN;
+    }
 #endif
 
 #ifdef KVM_CAP_MCE