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KVM: VMX: Add instruction rdtscp support for guest 

Before enabling, execution of "rdtscp" in guest would result in #UD.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
hifive-unleashed-5.1
Sheng Yang 2009-12-18 16:48:47 +08:00 committed by Marcelo Tosatti
parent 0e85188049
commit 4e47c7a6d7
5 changed files with 68 additions and 4 deletions
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1
arch/x86/include/asm/kvm_host.h
View File

@ -521,6 +521,7 @@ struct kvm_x86_ops {
int (*get_tdp_level)(void);
u64 (*get_mt_mask)(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
bool (*gb_page_enable)(void);
bool (*rdtscp_supported)(void);
const struct trace_print_flags *exit_reasons_str;
};

1
arch/x86/include/asm/vmx.h
View File

@ -53,6 +53,7 @@
*/
#define SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES 0x00000001
#define SECONDARY_EXEC_ENABLE_EPT 0x00000002
#define SECONDARY_EXEC_RDTSCP 0x00000008
#define SECONDARY_EXEC_ENABLE_VPID 0x00000020
#define SECONDARY_EXEC_WBINVD_EXITING 0x00000040
#define SECONDARY_EXEC_UNRESTRICTED_GUEST 0x00000080

7
arch/x86/kvm/svm.c
View File

@ -2914,6 +2914,11 @@ static bool svm_gb_page_enable(void)
return true;
}
static bool svm_rdtscp_supported(void)
{
return false;
}
static struct kvm_x86_ops svm_x86_ops = {
.cpu_has_kvm_support = has_svm,
.disabled_by_bios = is_disabled,
@ -2982,6 +2987,8 @@ static struct kvm_x86_ops svm_x86_ops = {
.gb_page_enable = svm_gb_page_enable,
.cpuid_update = svm_cpuid_update,
.rdtscp_supported = svm_rdtscp_supported,
};
static int __init svm_init(void)

60
arch/x86/kvm/vmx.c
View File

@ -151,6 +151,8 @@ struct vcpu_vmx {
ktime_t entry_time;
s64 vnmi_blocked_time;
u32 exit_reason;
bool rdtscp_enabled;
};
static inline struct vcpu_vmx *to_vmx(struct kvm_vcpu *vcpu)
@ -225,7 +227,7 @@ static const u32 vmx_msr_index[] = {
#ifdef CONFIG_X86_64
MSR_SYSCALL_MASK, MSR_LSTAR, MSR_CSTAR,
#endif
MSR_EFER, MSR_K6_STAR,
MSR_EFER, MSR_TSC_AUX, MSR_K6_STAR,
};
#define NR_VMX_MSR ARRAY_SIZE(vmx_msr_index)
@ -362,6 +364,12 @@ static inline int cpu_has_vmx_vpid(void)
SECONDARY_EXEC_ENABLE_VPID;
}
static inline int cpu_has_vmx_rdtscp(void)
{
return vmcs_config.cpu_based_2nd_exec_ctrl &
SECONDARY_EXEC_RDTSCP;
}
static inline int cpu_has_virtual_nmis(void)
{
return vmcs_config.pin_based_exec_ctrl & PIN_BASED_VIRTUAL_NMIS;
@ -893,6 +901,11 @@ static void vmx_queue_exception(struct kvm_vcpu *vcpu, unsigned nr,
vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, intr_info);
}
static bool vmx_rdtscp_supported(void)
{
return cpu_has_vmx_rdtscp();
}
/*
* Swap MSR entry in host/guest MSR entry array.
*/
@ -928,6 +941,9 @@ static void setup_msrs(struct vcpu_vmx *vmx)
index = __find_msr_index(vmx, MSR_CSTAR);
if (index >= 0)
move_msr_up(vmx, index, save_nmsrs++);
index = __find_msr_index(vmx, MSR_TSC_AUX);
if (index >= 0 && vmx->rdtscp_enabled)
move_msr_up(vmx, index, save_nmsrs++);
/*
* MSR_K6_STAR is only needed on long mode guests, and only
* if efer.sce is enabled.
@ -1017,6 +1033,10 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata)
case MSR_IA32_SYSENTER_ESP:
data = vmcs_readl(GUEST_SYSENTER_ESP);
break;
case MSR_TSC_AUX:
if (!to_vmx(vcpu)->rdtscp_enabled)
return 1;
/* Otherwise falls through */
default:
vmx_load_host_state(to_vmx(vcpu));
msr = find_msr_entry(to_vmx(vcpu), msr_index);
@ -1080,7 +1100,15 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
vcpu->arch.pat = data;
break;
}
/* Otherwise falls through to kvm_set_msr_common */
ret = kvm_set_msr_common(vcpu, msr_index, data);
break;
case MSR_TSC_AUX:
if (!vmx->rdtscp_enabled)
return 1;
/* Check reserved bit, higher 32 bits should be zero */
if ((data >> 32) != 0)
return 1;
/* Otherwise falls through */
default:
msr = find_msr_entry(vmx, msr_index);
if (msr) {
@ -1260,7 +1288,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf)
SECONDARY_EXEC_ENABLE_VPID |
SECONDARY_EXEC_ENABLE_EPT |
SECONDARY_EXEC_UNRESTRICTED_GUEST |
SECONDARY_EXEC_PAUSE_LOOP_EXITING;
SECONDARY_EXEC_PAUSE_LOOP_EXITING |
SECONDARY_EXEC_RDTSCP;
if (adjust_vmx_controls(min2, opt2,
MSR_IA32_VMX_PROCBASED_CTLS2,
&_cpu_based_2nd_exec_control) < 0)
@ -3988,8 +4017,31 @@ static bool vmx_gb_page_enable(void)
return false;
}
static inline u32 bit(int bitno)
{
return 1 << (bitno & 31);
}
static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
struct vcpu_vmx *vmx = to_vmx(vcpu);
u32 exec_control;
vmx->rdtscp_enabled = false;
if (vmx_rdtscp_supported()) {
exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL);
if (exec_control & SECONDARY_EXEC_RDTSCP) {
best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0);
if (best && (best->edx & bit(X86_FEATURE_RDTSCP)))
vmx->rdtscp_enabled = true;
else {
exec_control &= ~SECONDARY_EXEC_RDTSCP;
vmcs_write32(SECONDARY_VM_EXEC_CONTROL,
exec_control);
}
}
}
}
static struct kvm_x86_ops vmx_x86_ops = {
@ -4058,6 +4110,8 @@ static struct kvm_x86_ops vmx_x86_ops = {
.gb_page_enable = vmx_gb_page_enable,
.cpuid_update = vmx_cpuid_update,
.rdtscp_supported = vmx_rdtscp_supported,
};
static int __init vmx_init(void)

3
arch/x86/kvm/x86.c
View File

@ -1646,6 +1646,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
#else
unsigned f_lm = 0;
#endif
unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
/* cpuid 1.edx */
const u32 kvm_supported_word0_x86_features =
@ -1665,7 +1666,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
F(PAT) | F(PSE36) | 0 /* Reserved */ |
f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
F(FXSR) | F(FXSR_OPT) | f_gbpages | 0 /* RDTSCP */ |
F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
/* cpuid 1.ecx */
const u32 kvm_supported_word4_x86_features =