File 0138-target-i386-kvm-Don-t-enable-MONITO.patch of Package qemu.4227

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File 0138-target-i386-kvm-Don-t-enable-MONITO.patch of Package qemu.4227

From c9fb113b96c699861a43dc3b860db605cc544344 Mon Sep 17 00:00:00 2001
From: Eduardo Habkost <ehabkost@redhat.com>
Date: Wed, 30 Apr 2014 13:48:28 -0300
Subject: [PATCH] target-i386: kvm: Don't enable MONITOR by default on any CPU
 model
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KVM never supported the MONITOR flag so it doesn't make sense to have it
enabled by default when KVM is enabled.

The rationale here is similar to the cases where it makes sense to have
a feature enabled by default on all CPU models when on KVM mode (e.g.
x2apic). In this case we are having a feature disabled by default for
the same reasons.

In this case we don't need machine-type compat code because it is
currently impossible to run a KVM VM with the MONITOR flag set.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
(cherry picked from commit 136a7e9a85d7047461f8153f7d12c514a3d68f69)
[BR: BNC#895369]
Signed-off-by: Bruce Rogers <brogers@suse.com>
---
 target-i386/cpu.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 3326cdfe1a..27cb0edfe5 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -372,6 +372,12 @@ static uint32_t kvm_default_features[FEATURE_WORDS] = {
     [FEAT_1_ECX] = CPUID_EXT_X2APIC,
 };
 
+/* Features that are not added by default to any CPU model when KVM is enabled.
+ */
+static uint32_t kvm_default_unset_features[FEATURE_WORDS] = {
+    [FEAT_1_ECX] = CPUID_EXT_MONITOR,
+};
+
 void x86_cpu_compat_disable_kvm_features(FeatureWord w, uint32_t features)
 {
     kvm_default_features[w] &= ~features;
@@ -1893,6 +1899,7 @@ static void x86_cpu_load_def(X86CPU *cpu, X86CPUDefinition *def, Error **errp)
         FeatureWord w;
         for (w = 0; w < FEATURE_WORDS; w++) {
             env->features[w] |= kvm_default_features[w];
+            env->features[w] &= ~kvm_default_unset_features[w];
         }
     }

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File 0138-target-i386-kvm-Don-t-enable-MONITO.patch of Package qemu.4227

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