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| author | Joerg Roedel <joerg.roedel@amd.com> | 2008-02-13 20:58:47 +0300 |
|---|---|---|
| committer | Avi Kivity <avi@qumranet.com> | 2008-04-27 12:53:21 +0400 |
| commit | 24e09cbf480a72f9c952af4ca77b159503dca44b (patch) | |
| tree | f1f321963c620d26172f8fd0878374d9598c0ad0 | |
| parent | f65c229c3e7743c6654c16b9ec6248466b5eef21 (diff) | |
| download | linux-24e09cbf480a72f9c952af4ca77b159503dca44b.tar.xz | |
KVM: SVM: enable LBR virtualization
This patch implements the Last Branch Record Virtualization (LBRV) feature of
the AMD Barcelona and Phenom processors into the kvm-amd module. It will only
be enabled if the guest enables last branch recording in the DEBUG_CTL MSR. So
there is no increased world switch overhead when the guest doesn't use these
MSRs.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Markus Rechberger <markus.rechberger@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
| -rw-r--r-- | arch/x86/kvm/svm.c | 39 |
1 files changed, 37 insertions, 2 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 281a2ffe1224..7d73e935dcc1 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -47,6 +47,8 @@ MODULE_LICENSE("GPL"); #define SVM_FEATURE_LBRV (1 << 1) #define SVM_DEATURE_SVML (1 << 2) +#define DEBUGCTL_RESERVED_BITS (~(0x3fULL)) + /* enable NPT for AMD64 and X86 with PAE */ #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) static bool npt_enabled = true; @@ -387,6 +389,28 @@ static void svm_vcpu_init_msrpm(u32 *msrpm) set_msr_interception(msrpm, MSR_IA32_SYSENTER_EIP, 1, 1); } +static void svm_enable_lbrv(struct vcpu_svm *svm) +{ + u32 *msrpm = svm->msrpm; + + svm->vmcb->control.lbr_ctl = 1; + 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); + set_msr_interception(msrpm, MSR_IA32_LASTINTTOIP, 1, 1); +} + +static void svm_disable_lbrv(struct vcpu_svm *svm) +{ + u32 *msrpm = svm->msrpm; + + svm->vmcb->control.lbr_ctl = 0; + 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); + set_msr_interception(msrpm, MSR_IA32_LASTINTTOIP, 0, 0); +} + static __init int svm_hardware_setup(void) { int cpu; @@ -1231,8 +1255,19 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 data) svm->vmcb->save.sysenter_esp = data; break; case MSR_IA32_DEBUGCTLMSR: - pr_unimpl(vcpu, "%s: MSR_IA32_DEBUGCTLMSR 0x%llx, nop\n", - __FUNCTION__, data); + if (!svm_has(SVM_FEATURE_LBRV)) { + pr_unimpl(vcpu, "%s: MSR_IA32_DEBUGCTL 0x%llx, nop\n", + __FUNCTION__, data); + break; + } + if (data & DEBUGCTL_RESERVED_BITS) + return 1; + + svm->vmcb->save.dbgctl = data; + if (data & (1ULL<<0)) + svm_enable_lbrv(svm); + else + svm_disable_lbrv(svm); break; case MSR_K7_EVNTSEL0: case MSR_K7_EVNTSEL1: |