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authorJanakarajan Natarajan <Janakarajan.Natarajan@amd.com>2017-07-06 15:50:44 -0500
committerRadim Krčmář <rkrcmar@redhat.com>2017-07-12 22:38:28 +0200
commit8a77e90966e92759f94087f9845d413290be0d70 (patch)
tree17bb4aae92b4ebf1aa096e25c7df0d25d70cc252 /arch/x86
parentb742c1e6e79ddf4192d76336da2407c65ca7242f (diff)
downloadlinux-8a77e90966e92759f94087f9845d413290be0d70.tar.bz2
KVM: SVM: Prepare for new bit definition in lbr_ctl
The lbr_ctl variable in the vmcb control area is used to enable or disable Last Branch Record (LBR) virtualization. However, this is to be done using only bit 0 of the variable. To correct this and to prepare for a new feature, change the current usage to work only on a particular bit. Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/include/asm/svm.h2
-rw-r--r--arch/x86/kvm/svm.c4
2 files changed, 4 insertions, 2 deletions
diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 14824fc78f7e..d1163f64d732 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -119,6 +119,8 @@ struct __attribute__ ((__packed__)) vmcb_control_area {
#define AVIC_ENABLE_SHIFT 31
#define AVIC_ENABLE_MASK (1 << AVIC_ENABLE_SHIFT)
+#define LBR_CTL_ENABLE_MASK BIT_ULL(0)
+
#define SVM_INTERRUPT_SHADOW_MASK 1
#define SVM_IOIO_STR_SHIFT 2
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 3da42d7c629e..6e72127c0d0e 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -947,7 +947,7 @@ static void svm_enable_lbrv(struct vcpu_svm *svm)
{
u32 *msrpm = svm->msrpm;
- svm->vmcb->control.lbr_ctl = 1;
+ svm->vmcb->control.lbr_ctl |= LBR_CTL_ENABLE_MASK;
set_msr_interception(msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1);
set_msr_interception(msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1);
set_msr_interception(msrpm, MSR_IA32_LASTINTFROMIP, 1, 1);
@@ -958,7 +958,7 @@ static void svm_disable_lbrv(struct vcpu_svm *svm)
{
u32 *msrpm = svm->msrpm;
- svm->vmcb->control.lbr_ctl = 0;
+ svm->vmcb->control.lbr_ctl &= ~LBR_CTL_ENABLE_MASK;
set_msr_interception(msrpm, MSR_IA32_LASTBRANCHFROMIP, 0, 0);
set_msr_interception(msrpm, MSR_IA32_LASTBRANCHTOIP, 0, 0);
set_msr_interception(msrpm, MSR_IA32_LASTINTFROMIP, 0, 0);