[PATCH v3 4/9] KVM: x86: Add Intel Processor Trace cpuid emulation
From: Luwei Kang
Date: Tue Nov 28 2017 - 05:09:37 EST
From: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>
Expose Intel Processor Trace to guest only when PT work in
HOST_GUEST mode.
Signed-off-by: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>
Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/include/asm/cpufeatures.h | 2 +-
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kernel/cpu/scattered.c | 1 -
arch/x86/kvm/cpuid.c | 22 ++++++++++++++++++++--
arch/x86/kvm/svm.c | 6 ++++++
arch/x86/kvm/vmx.c | 6 ++++++
6 files changed, 34 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index c0b0e9e..3e03cbe 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -203,7 +203,6 @@
#define X86_FEATURE_SME ( 7*32+10) /* AMD Secure Memory Encryption */
#define X86_FEATURE_INTEL_PPIN ( 7*32+14) /* Intel Processor Inventory Number */
-#define X86_FEATURE_INTEL_PT ( 7*32+15) /* Intel Processor Trace */
#define X86_FEATURE_AVX512_4VNNIW ( 7*32+16) /* AVX-512 Neural Network Instructions */
#define X86_FEATURE_AVX512_4FMAPS ( 7*32+17) /* AVX-512 Multiply Accumulation Single precision */
@@ -242,6 +241,7 @@
#define X86_FEATURE_AVX512IFMA ( 9*32+21) /* AVX-512 Integer Fused Multiply-Add instructions */
#define X86_FEATURE_CLFLUSHOPT ( 9*32+23) /* CLFLUSHOPT instruction */
#define X86_FEATURE_CLWB ( 9*32+24) /* CLWB instruction */
+#define X86_FEATURE_INTEL_PT ( 9*32+25) /* Intel Processor Trace */
#define X86_FEATURE_AVX512PF ( 9*32+26) /* AVX-512 Prefetch */
#define X86_FEATURE_AVX512ER ( 9*32+27) /* AVX-512 Exponential and Reciprocal */
#define X86_FEATURE_AVX512CD ( 9*32+28) /* AVX-512 Conflict Detection */
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 1bfb997..d0b99ae 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1004,6 +1004,7 @@ struct kvm_x86_ops {
void (*handle_external_intr)(struct kvm_vcpu *vcpu);
bool (*mpx_supported)(void);
bool (*xsaves_supported)(void);
+ bool (*pt_supported)(void);
int (*check_nested_events)(struct kvm_vcpu *vcpu, bool external_intr);
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 05459ad..d0e6976 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -21,7 +21,6 @@ struct cpuid_bit {
static const struct cpuid_bit cpuid_bits[] = {
{ X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 },
{ X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 },
- { X86_FEATURE_INTEL_PT, CPUID_EBX, 25, 0x00000007, 0 },
{ X86_FEATURE_AVX512_4VNNIW, CPUID_EDX, 2, 0x00000007, 0 },
{ X86_FEATURE_AVX512_4FMAPS, CPUID_EDX, 3, 0x00000007, 0 },
{ X86_FEATURE_CAT_L3, CPUID_EBX, 1, 0x00000010, 0 },
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 0099e10..608794f 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -327,6 +327,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
unsigned f_mpx = kvm_mpx_supported() ? F(MPX) : 0;
unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0;
+ unsigned f_intel_pt = kvm_x86_ops->pt_supported() ? F(INTEL_PT) : 0;
/* cpuid 1.edx */
const u32 kvm_cpuid_1_edx_x86_features =
@@ -379,7 +380,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
F(ADX) | F(SMAP) | F(AVX512IFMA) | F(AVX512F) | F(AVX512PF) |
F(AVX512ER) | F(AVX512CD) | F(CLFLUSHOPT) | F(CLWB) | F(AVX512DQ) |
- F(SHA_NI) | F(AVX512BW) | F(AVX512VL);
+ F(SHA_NI) | F(AVX512BW) | F(AVX512VL) | f_intel_pt;
/* cpuid 0xD.1.eax */
const u32 kvm_cpuid_D_1_eax_x86_features =
@@ -407,7 +408,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
switch (function) {
case 0:
- entry->eax = min(entry->eax, (u32)0xd);
+ entry->eax = min(entry->eax, (u32)(f_intel_pt ? 0x14 : 0xd));
break;
case 1:
entry->edx &= kvm_cpuid_1_edx_x86_features;
@@ -578,6 +579,23 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
}
break;
}
+ /* Intel PT */
+ case 0x14: {
+ int t, times = entry->eax & 0xffffffff;
+
+ if (!f_intel_pt)
+ break;
+
+ entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+ for (t = 1; t <= times; ++t) {
+ if (*nent >= maxnent)
+ goto out;
+ do_cpuid_1_ent(&entry[t], function, t);
+ entry[t].flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+ ++*nent;
+ }
+ break;
+ }
case KVM_CPUID_SIGNATURE: {
static const char signature[12] = "KVMKVMKVM\0\0";
const u32 *sigptr = (const u32 *)signature;
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 59e13a7..c579272 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -5195,6 +5195,11 @@ static bool svm_xsaves_supported(void)
return false;
}
+static bool svm_pt_supported(void)
+{
+ return false;
+}
+
static bool svm_has_wbinvd_exit(void)
{
return true;
@@ -5588,6 +5593,7 @@ static int enable_smi_window(struct kvm_vcpu *vcpu)
.invpcid_supported = svm_invpcid_supported,
.mpx_supported = svm_mpx_supported,
.xsaves_supported = svm_xsaves_supported,
+ .pt_supported = svm_pt_supported,
.set_supported_cpuid = svm_set_supported_cpuid,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 73da8a2..d8ad68a 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -9219,6 +9219,11 @@ static bool vmx_xsaves_supported(void)
SECONDARY_EXEC_XSAVES;
}
+static bool vmx_pt_supported(void)
+{
+ return (pt_mode == PT_MODE_HOST_GUEST);
+}
+
static void vmx_recover_nmi_blocking(struct vcpu_vmx *vmx)
{
u32 exit_intr_info;
@@ -12221,6 +12226,7 @@ static int enable_smi_window(struct kvm_vcpu *vcpu)
.handle_external_intr = vmx_handle_external_intr,
.mpx_supported = vmx_mpx_supported,
.xsaves_supported = vmx_xsaves_supported,
+ .pt_supported = vmx_pt_supported,
.check_nested_events = vmx_check_nested_events,
--
1.8.3.1