From: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>
Expose Intel Processor Trace feature to guest.
To make Intel PT live migration safe and get same CPUID information
with same CPU model on diffrent host. CPUID[14] is constant in this
patch. Intel PT use EPT is first supported in IceLake, the CPUID[14]
get on this machine as default value. Intel PT would be disabled
if any machine don't support this minial feature list.
Signed-off-by: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>
Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>
---
>From V3:
- fix some typo;
- add some comments and safty check.
---
target/i386/cpu.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
target/i386/cpu.h | 1 +
target/i386/kvm.c | 23 ++++++++++++++++
3 files changed, 100 insertions(+), 2 deletions(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index b5e431e..24e1693 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -173,7 +173,32 @@
#define L2_ITLB_4K_ASSOC 4
#define L2_ITLB_4K_ENTRIES 512
-
+/* CPUID Leaf 0x14 constants: */
+#define INTEL_PT_MAX_SUBLEAF 0x1
+/*
+ * bit[00]: IA32_RTIT_CTL.CR3 filter can be set to 1 and IA32_RTIT_CR3_MATCH
+ * MSR can be accessed;
+ * bit[01]: Support Configurable PSB and Cycle-Accurate Mode;
+ * bit[02]: Support IP Filtering, TraceStop filtering, and preservation
+ * of Intel PT MSRs across warm reset;
+ * bit[03]: Support MTC timing packet and suppression of COFI-based packets;
+ */
+#define INTEL_PT_MINIMAL_EBX 0xf
+/*
+ * bit[00]: Tracing can be enabled with IA32_RTIT_CTL.ToPA = 1 and
+ * IA32_RTIT_OUTPUT_BASE and IA32_RTIT_OUTPUT_MASK_PTRS MSRs can be
+ * accessed;
+ * bit[01]: ToPA tables can hold any number of output entries, up to the
+ * maximum allowed by the MaskOrTableOffset field of
+ * IA32_RTIT_OUTPUT_MASK_PTRS;
+ * bit[02]: Support Single-Range Output scheme;
+ */
+#define INTEL_PT_MINIMAL_ECX 0x7
+#define INTEL_PT_ADDR_RANGES_NUM 0x2 /* Number of configurable address ranges */
+#define INTEL_PT_ADDR_RANGES_NUM_MASK 0x3
+#define INTEL_PT_MTC_BITMAP (0x0249 << 16) /* Support ART(0,3,6,9) */
+#define INTEL_PT_CYCLE_BITMAP 0x1fff /* Support 0,2^(0~11) */
+#define INTEL_PT_PSB_BITMAP (0x003f << 16) /* Support 2K,4K,8K,16K,32K,64K */
static void x86_cpu_vendor_words2str(char *dst, uint32_t vendor1,
uint32_t vendor2, uint32_t vendor3)
@@ -428,7 +453,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
NULL, NULL, "mpx", NULL,
"avx512f", "avx512dq", "rdseed", "adx",
"smap", "avx512ifma", "pcommit", "clflushopt",
- "clwb", NULL, "avx512pf", "avx512er",
+ "clwb", "intel-pt", "avx512pf", "avx512er",
"avx512cd", "sha-ni", "avx512bw", "avx512vl",
},
.cpuid_eax = 7,
@@ -3453,6 +3478,27 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
}
break;
}
+ case 0x14: {
+ /* Intel Processor Trace Enumeration */
+ *eax = 0;
+ *ebx = 0;
+ *ecx = 0;
+ *edx = 0;
+ if (!(env->features[FEAT_7_0_EBX] & CPUID_7_0_EBX_INTEL_PT) ||
+ !kvm_enabled()) {
+ break;
+ }
+
+ if (count == 0) {
+ *eax = INTEL_PT_MAX_SUBLEAF;
+ *ebx = INTEL_PT_MINIMAL_EBX;
+ *ecx = INTEL_PT_MINIMAL_ECX;
+ } else if (count == 1) {
+ *eax = INTEL_PT_MTC_BITMAP | INTEL_PT_ADDR_RANGES_NUM;
+ *ebx = INTEL_PT_PSB_BITMAP | INTEL_PT_CYCLE_BITMAP;
+ }
+ break;
+ }
case 0x40000000:
/*
* CPUID code in kvm_arch_init_vcpu() ignores stuff
@@ -4083,6 +4129,34 @@ static int x86_cpu_filter_features(X86CPU *cpu)
}
}
+ if ((env->features[FEAT_7_0_EBX] & CPUID_7_0_EBX_INTEL_PT) &&
+ kvm_enabled()) {
+ KVMState *s = CPU(cpu)->kvm_state;
+ uint32_t eax_0 = kvm_arch_get_supported_cpuid(s, 0x14, 0, R_EAX);
+ uint32_t ebx_0 = kvm_arch_get_supported_cpuid(s, 0x14, 0, R_EBX);
+ uint32_t ecx_0 = kvm_arch_get_supported_cpuid(s, 0x14, 0, R_ECX);
+ uint32_t eax_1 = kvm_arch_get_supported_cpuid(s, 0x14, 1, R_EAX);
+ uint32_t ebx_1 = kvm_arch_get_supported_cpuid(s, 0x14, 1, R_EBX);
+
+ if (!eax_0 ||
+ ((ebx_0 & INTEL_PT_MINIMAL_EBX) != INTEL_PT_MINIMAL_EBX) ||
+ ((ecx_0 & INTEL_PT_MINIMAL_ECX) != INTEL_PT_MINIMAL_ECX) ||
+ ((eax_1 & INTEL_PT_MTC_BITMAP) != INTEL_PT_MTC_BITMAP) ||
+ ((eax_1 & INTEL_PT_ADDR_RANGES_NUM_MASK) <
+ INTEL_PT_ADDR_RANGES_NUM) ||
+ ((ebx_1 & (INTEL_PT_PSB_BITMAP | INTEL_PT_CYCLE_BITMAP)) !=
+ (INTEL_PT_PSB_BITMAP | INTEL_PT_CYCLE_BITMAP))) {
+ /*
+ * Processor Trace capabilities aren't configurable, so if the
+ * host can't emulate the capabilities we report on
+ * cpu_x86_cpuid(), intel-pt can't be enabled on the current host.
+ */
+ env->features[FEAT_7_0_EBX] &= ~CPUID_7_0_EBX_INTEL_PT;
+ cpu->filtered_features[FEAT_7_0_EBX] |= CPUID_7_0_EBX_INTEL_PT;
+ rv = 1;
+ }
+ }
+
return rv;
}
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index faf39ec..f5b9ecb 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -640,6 +640,7 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS];
#define CPUID_7_0_EBX_PCOMMIT (1U << 22) /* Persistent Commit */
#define CPUID_7_0_EBX_CLFLUSHOPT (1U << 23) /* Flush a Cache Line Optimized */
#define CPUID_7_0_EBX_CLWB (1U << 24) /* Cache Line Write Back */
+#define CPUID_7_0_EBX_INTEL_PT (1U << 25) /* Intel Processor Trace */
#define CPUID_7_0_EBX_AVX512PF (1U << 26) /* AVX-512 Prefetch */
#define CPUID_7_0_EBX_AVX512ER (1U << 27) /* AVX-512 Exponential and Reciprocal */
#define CPUID_7_0_EBX_AVX512CD (1U << 28) /* AVX-512 Conflict Detection */
diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index ad4b159..f9f4cd1 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -865,6 +865,29 @@ int kvm_arch_init_vcpu(CPUState *cs)
c = &cpuid_data.entries[cpuid_i++];
}
break;
+ case 0x14: {
+ uint32_t times;
+
+ c->function = i;
+ c->index = 0;
+ c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+ cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
+ times = c->eax;
+
+ for (j = 1; j <= times; ++j) {
+ if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
+ fprintf(stderr, "cpuid_data is full, no space for "
+ "cpuid(eax:0x14,ecx:0x%x)\n", j);
+ abort();
+ }
+ c = &cpuid_data.entries[cpuid_i++];
+ c->function = i;
+ c->index = j;
+ c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+ cpu_x86_cpuid(env, i, j, &c->eax, &c->ebx, &c->ecx, &c->edx);
+ }
+ break;
+ }
default:
c->function = i;
c->flags = 0;
--
1.8.3.1
