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KVM: x86: generalize guest_cpuid_has_ helpers
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This patch turns guest_cpuid_has_XYZ(cpuid) into guest_cpuid_has(cpuid,
X86_FEATURE_XYZ), which gets rid of many very similar helpers.

When seeing a X86_FEATURE_*, we can know which cpuid it belongs to, but
this information isn't in common code, so we recreate it for KVM.

Add some BUILD_BUG_ONs to make sure that it runs nicely.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Radim Krčmář authored and Paolo Bonzini committed Aug 7, 2017
1 parent c6bd180 commit d6321d4
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Showing 6 changed files with 95 additions and 150 deletions.
170 changes: 57 additions & 113 deletions arch/x86/kvm/cpuid.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,7 @@

#include "x86.h"
#include <asm/cpu.h>
#include <asm/processor.h>

int kvm_update_cpuid(struct kvm_vcpu *vcpu);
bool kvm_mpx_supported(void);
Expand All @@ -29,95 +30,78 @@ static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
return vcpu->arch.maxphyaddr;
}

static inline bool guest_cpuid_has_xsave(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
struct cpuid_reg {
u32 function;
u32 index;
int reg;
};

if (!static_cpu_has(X86_FEATURE_XSAVE))
return false;

best = kvm_find_cpuid_entry(vcpu, 1, 0);
return best && (best->ecx & bit(X86_FEATURE_XSAVE));
}
static const struct cpuid_reg reverse_cpuid[] = {
[CPUID_1_EDX] = { 1, 0, CPUID_EDX},
[CPUID_8000_0001_EDX] = {0x80000001, 0, CPUID_EDX},
[CPUID_8086_0001_EDX] = {0x80860001, 0, CPUID_EDX},
[CPUID_1_ECX] = { 1, 0, CPUID_ECX},
[CPUID_C000_0001_EDX] = {0xc0000001, 0, CPUID_EDX},
[CPUID_8000_0001_ECX] = {0xc0000001, 0, CPUID_ECX},
[CPUID_7_0_EBX] = { 7, 0, CPUID_EBX},
[CPUID_D_1_EAX] = { 0xd, 1, CPUID_EAX},
[CPUID_F_0_EDX] = { 0xf, 0, CPUID_EDX},
[CPUID_F_1_EDX] = { 0xf, 1, CPUID_EDX},
[CPUID_8000_0008_EBX] = {0x80000008, 0, CPUID_EBX},
[CPUID_6_EAX] = { 6, 0, CPUID_EAX},
[CPUID_8000_000A_EDX] = {0x8000000a, 0, CPUID_EDX},
[CPUID_7_ECX] = { 7, 0, CPUID_ECX},
[CPUID_8000_0007_EBX] = {0x80000007, 0, CPUID_EBX},
};

static inline bool guest_cpuid_has_mtrr(struct kvm_vcpu *vcpu)
static __always_inline struct cpuid_reg x86_feature_cpuid(unsigned x86_feature)
{
struct kvm_cpuid_entry2 *best;
unsigned x86_leaf = x86_feature / 32;

best = kvm_find_cpuid_entry(vcpu, 1, 0);
return best && (best->edx & bit(X86_FEATURE_MTRR));
}
BUILD_BUG_ON(!__builtin_constant_p(x86_leaf));
BUILD_BUG_ON(x86_leaf >= ARRAY_SIZE(reverse_cpuid));
BUILD_BUG_ON(reverse_cpuid[x86_leaf].function == 0);

static inline bool guest_cpuid_has_tsc_adjust(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 7, 0);
return best && (best->ebx & bit(X86_FEATURE_TSC_ADJUST));
}

static inline bool guest_cpuid_has_smep(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 7, 0);
return best && (best->ebx & bit(X86_FEATURE_SMEP));
return reverse_cpuid[x86_leaf];
}

static inline bool guest_cpuid_has_smap(struct kvm_vcpu *vcpu)
static __always_inline int *guest_cpuid_get_register(struct kvm_vcpu *vcpu, unsigned x86_feature)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 7, 0);
return best && (best->ebx & bit(X86_FEATURE_SMAP));
}

static inline bool guest_cpuid_has_fsgsbase(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 7, 0);
return best && (best->ebx & bit(X86_FEATURE_FSGSBASE));
}

static inline bool guest_cpuid_has_pku(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 7, 0);
return best && (best->ecx & bit(X86_FEATURE_PKU));
}

static inline bool guest_cpuid_has_longmode(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0);
return best && (best->edx & bit(X86_FEATURE_LM));
}
struct kvm_cpuid_entry2 *entry;
const struct cpuid_reg cpuid = x86_feature_cpuid(x86_feature);

static inline bool guest_cpuid_has_osvw(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
entry = kvm_find_cpuid_entry(vcpu, cpuid.function, cpuid.index);
if (!entry)
return NULL;

best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0);
return best && (best->ecx & bit(X86_FEATURE_OSVW));
switch (cpuid.reg) {
case CPUID_EAX:
return &entry->eax;
case CPUID_EBX:
return &entry->ebx;
case CPUID_ECX:
return &entry->ecx;
case CPUID_EDX:
return &entry->edx;
default:
BUILD_BUG();
return NULL;
}
}

static inline bool guest_cpuid_has_pcid(struct kvm_vcpu *vcpu)
static __always_inline bool guest_cpuid_has(struct kvm_vcpu *vcpu, unsigned x86_feature)
{
struct kvm_cpuid_entry2 *best;
int *reg;

best = kvm_find_cpuid_entry(vcpu, 1, 0);
return best && (best->ecx & bit(X86_FEATURE_PCID));
}
if (x86_feature == X86_FEATURE_XSAVE &&
!static_cpu_has(X86_FEATURE_XSAVE))
return false;

static inline bool guest_cpuid_has_x2apic(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
reg = guest_cpuid_get_register(vcpu, x86_feature);
if (!reg)
return false;

best = kvm_find_cpuid_entry(vcpu, 1, 0);
return best && (best->ecx & bit(X86_FEATURE_X2APIC));
return *reg & bit(x86_feature);
}

static inline bool guest_cpuid_is_amd(struct kvm_vcpu *vcpu)
Expand All @@ -128,46 +112,6 @@ static inline bool guest_cpuid_is_amd(struct kvm_vcpu *vcpu)
return best && best->ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx;
}

static inline bool guest_cpuid_has_gbpages(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0);
return best && (best->edx & bit(X86_FEATURE_GBPAGES));
}

static inline bool guest_cpuid_has_rtm(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 7, 0);
return best && (best->ebx & bit(X86_FEATURE_RTM));
}

static inline bool guest_cpuid_has_mpx(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 7, 0);
return best && (best->ebx & bit(X86_FEATURE_MPX));
}

static inline bool guest_cpuid_has_rdtscp(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0);
return best && (best->edx & bit(X86_FEATURE_RDTSCP));
}

static inline bool guest_cpuid_has_nrips(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 0x8000000a, 0);
return best && (best->edx & bit(X86_FEATURE_NRIPS));
}

static inline int guest_cpuid_family(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
Expand Down
7 changes: 4 additions & 3 deletions arch/x86/kvm/mmu.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4052,7 +4052,8 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu,
{
__reset_rsvds_bits_mask(vcpu, &context->guest_rsvd_check,
cpuid_maxphyaddr(vcpu), context->root_level,
context->nx, guest_cpuid_has_gbpages(vcpu),
context->nx,
guest_cpuid_has(vcpu, X86_FEATURE_GBPAGES),
is_pse(vcpu), guest_cpuid_is_amd(vcpu));
}

Expand Down Expand Up @@ -4114,8 +4115,8 @@ reset_shadow_zero_bits_mask(struct kvm_vcpu *vcpu, struct kvm_mmu *context)
__reset_rsvds_bits_mask(vcpu, &context->shadow_zero_check,
boot_cpu_data.x86_phys_bits,
context->shadow_root_level, uses_nx,
guest_cpuid_has_gbpages(vcpu), is_pse(vcpu),
true);
guest_cpuid_has(vcpu, X86_FEATURE_GBPAGES),
is_pse(vcpu), true);
}
EXPORT_SYMBOL_GPL(reset_shadow_zero_bits_mask);

Expand Down
2 changes: 1 addition & 1 deletion arch/x86/kvm/mtrr.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -130,7 +130,7 @@ static u8 mtrr_disabled_type(struct kvm_vcpu *vcpu)
* enable MTRRs and it is obviously undesirable to run the
* guest entirely with UC memory and we use WB.
*/
if (guest_cpuid_has_mtrr(vcpu))
if (guest_cpuid_has(vcpu, X86_FEATURE_MTRR))
return MTRR_TYPE_UNCACHABLE;
else
return MTRR_TYPE_WRBACK;
Expand Down
2 changes: 1 addition & 1 deletion arch/x86/kvm/svm.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -5078,7 +5078,7 @@ static void svm_cpuid_update(struct kvm_vcpu *vcpu)
struct kvm_cpuid_entry2 *entry;

/* Update nrips enabled cache */
svm->nrips_enabled = !!guest_cpuid_has_nrips(&svm->vcpu);
svm->nrips_enabled = !!guest_cpuid_has(&svm->vcpu, X86_FEATURE_NRIPS);

if (!kvm_vcpu_apicv_active(vcpu))
return;
Expand Down
26 changes: 12 additions & 14 deletions arch/x86/kvm/vmx.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2611,7 +2611,7 @@ static void setup_msrs(struct vcpu_vmx *vmx)
if (index >= 0)
move_msr_up(vmx, index, save_nmsrs++);
index = __find_msr_index(vmx, MSR_TSC_AUX);
if (index >= 0 && guest_cpuid_has_rdtscp(&vmx->vcpu))
if (index >= 0 && guest_cpuid_has(&vmx->vcpu, X86_FEATURE_RDTSCP))
move_msr_up(vmx, index, save_nmsrs++);
/*
* MSR_STAR is only needed on long mode guests, and only
Expand Down Expand Up @@ -2671,12 +2671,6 @@ static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
}
}

static bool guest_cpuid_has_vmx(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best = kvm_find_cpuid_entry(vcpu, 1, 0);
return best && (best->ecx & (1 << (X86_FEATURE_VMX & 31)));
}

/*
* nested_vmx_allowed() checks whether a guest should be allowed to use VMX
* instructions and MSRs (i.e., nested VMX). Nested VMX is disabled for
Expand All @@ -2685,7 +2679,7 @@ static bool guest_cpuid_has_vmx(struct kvm_vcpu *vcpu)
*/
static inline bool nested_vmx_allowed(struct kvm_vcpu *vcpu)
{
return nested && guest_cpuid_has_vmx(vcpu);
return nested && guest_cpuid_has(vcpu, X86_FEATURE_VMX);
}

/*
Expand Down Expand Up @@ -3281,7 +3275,8 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
break;
case MSR_IA32_BNDCFGS:
if (!kvm_mpx_supported() ||
(!msr_info->host_initiated && !guest_cpuid_has_mpx(vcpu)))
(!msr_info->host_initiated &&
!guest_cpuid_has(vcpu, X86_FEATURE_MPX)))
return 1;
msr_info->data = vmcs_read64(GUEST_BNDCFGS);
break;
Expand All @@ -3305,7 +3300,8 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
msr_info->data = vcpu->arch.ia32_xss;
break;
case MSR_TSC_AUX:
if (!guest_cpuid_has_rdtscp(vcpu) && !msr_info->host_initiated)
if (!msr_info->host_initiated &&
!guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP))
return 1;
/* Otherwise falls through */
default:
Expand Down Expand Up @@ -3364,7 +3360,8 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
break;
case MSR_IA32_BNDCFGS:
if (!kvm_mpx_supported() ||
(!msr_info->host_initiated && !guest_cpuid_has_mpx(vcpu)))
(!msr_info->host_initiated &&
!guest_cpuid_has(vcpu, X86_FEATURE_MPX)))
return 1;
if (is_noncanonical_address(data & PAGE_MASK) ||
(data & MSR_IA32_BNDCFGS_RSVD))
Expand Down Expand Up @@ -3427,7 +3424,8 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
clear_atomic_switch_msr(vmx, MSR_IA32_XSS);
break;
case MSR_TSC_AUX:
if (!guest_cpuid_has_rdtscp(vcpu) && !msr_info->host_initiated)
if (!msr_info->host_initiated &&
!guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP))
return 1;
/* Check reserved bit, higher 32 bits should be zero */
if ((data >> 32) != 0)
Expand Down Expand Up @@ -9622,7 +9620,7 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
u32 secondary_exec_ctl = vmx_secondary_exec_control(vmx);

if (vmx_rdtscp_supported()) {
bool rdtscp_enabled = guest_cpuid_has_rdtscp(vcpu);
bool rdtscp_enabled = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP);
if (!rdtscp_enabled)
secondary_exec_ctl &= ~SECONDARY_EXEC_RDTSCP;

Expand All @@ -9641,7 +9639,7 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
struct kvm_cpuid_entry2 *best = kvm_find_cpuid_entry(vcpu, 0x7, 0);
bool invpcid_enabled =
best && best->ebx & bit(X86_FEATURE_INVPCID) &&
guest_cpuid_has_pcid(vcpu);
guest_cpuid_has(vcpu, X86_FEATURE_PCID);

if (!invpcid_enabled) {
secondary_exec_ctl &= ~SECONDARY_EXEC_ENABLE_INVPCID;
Expand Down
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