[PATCH 20/26] KVM: x86: Handle PKU CPUID adjustment in SVM code

[Sean Christopherson]

Move the clearing of the PKU CPUID bit into SVM, which does not yet
support virtualizing PKU, to eliminate an instance of the undesirable
"unsigned f_* = *_supported ? F(*) : 0" pattern in the common CPUID
handling code.  Drop ->pku_supported() since CPUID adjustment was the
only user.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
---
 arch/x86/include/asm/kvm_host.h | 1 -
 arch/x86/kvm/cpuid.c            | 4 +---
 arch/x86/kvm/svm.c              | 7 +------
 arch/x86/kvm/vmx/capabilities.h | 5 -----
 arch/x86/kvm/vmx/vmx.c          | 1 -
 5 files changed, 2 insertions(+), 16 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b9c871c03bf5..8a685509c218 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1167,7 +1167,6 @@ struct kvm_x86_ops {
 	bool (*xsaves_supported)(void);
 	bool (*umip_emulated)(void);
 	bool (*pt_supported)(void);
-	bool (*pku_supported)(void);
 
 	int (*check_nested_events)(struct kvm_vcpu *vcpu, bool external_intr);
 	void (*request_immediate_exit)(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index d835f4662fba..e376d648f94d 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -323,7 +323,6 @@ static inline void do_cpuid_7_mask(struct kvm_cpuid_entry2 *entry, int index)
 {
 	unsigned f_intel_pt = kvm_x86_ops->pt_supported() ? F(INTEL_PT) : 0;
 	unsigned f_la57;
-	unsigned f_pku = kvm_x86_ops->pku_supported() ? F(PKU) : 0;
 
 	/* cpuid 7.0.ebx */
 	const u32 kvm_cpuid_7_0_ebx_x86_features =
@@ -335,7 +334,7 @@ static inline void do_cpuid_7_mask(struct kvm_cpuid_entry2 *entry, int index)
 
 	/* cpuid 7.0.ecx*/
 	const u32 kvm_cpuid_7_0_ecx_x86_features =
-		F(AVX512VBMI) | F(LA57) | 0 /*PKU*/ | 0 /*OSPKE*/ | F(RDPID) |
+		F(AVX512VBMI) | F(LA57) | F(PKU) | 0 /*OSPKE*/ | F(RDPID) |
 		F(AVX512_VPOPCNTDQ) | F(UMIP) | F(AVX512_VBMI2) | F(GFNI) |
 		F(VAES) | F(VPCLMULQDQ) | F(AVX512_VNNI) | F(AVX512_BITALG) |
 		F(CLDEMOTE) | F(MOVDIRI) | F(MOVDIR64B) | 0 /*WAITPKG*/;
@@ -363,7 +362,6 @@ static inline void do_cpuid_7_mask(struct kvm_cpuid_entry2 *entry, int index)
 		cpuid_mask(&entry->ecx, CPUID_7_ECX);
 		/* Set LA57 based on hardware capability. */
 		entry->ecx |= f_la57;
-		entry->ecx |= f_pku;
 		/* PKU is not yet implemented for shadow paging. */
 		if (!tdp_enabled || !boot_cpu_has(X86_FEATURE_OSPKE))
 			cpuid_entry_clear(entry, X86_FEATURE_PKU);
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 4ea530ff6a0c..1092d5e6c683 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -6060,6 +6060,7 @@ static void svm_set_supported_cpuid(struct kvm_cpuid_entry2 *entry)
 			cpuid_entry_clear(entry, X86_FEATURE_X2APIC);
 		break;
 	case 0x7:
+		cpuid_entry_clear(entry, X86_FEATURE_PKU);
 		cpuid_entry_clear(entry, X86_FEATURE_MPX);
 		cpuid_entry_clear(entry, X86_FEATURE_INVPCID);
 		break;
@@ -6120,11 +6121,6 @@ static bool svm_has_wbinvd_exit(void)
 	return true;
 }
 
-static bool svm_pku_supported(void)
-{
-	return false;
-}
-
 #define PRE_EX(exit)  { .exit_code = (exit), \
 			.stage = X86_ICPT_PRE_EXCEPT, }
 #define POST_EX(exit) { .exit_code = (exit), \
@@ -7484,7 +7480,6 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
 	.xsaves_supported = svm_xsaves_supported,
 	.umip_emulated = svm_umip_emulated,
 	.pt_supported = svm_pt_supported,
-	.pku_supported = svm_pku_supported,
 
 	.set_supported_cpuid = svm_set_supported_cpuid,
 
diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index 0a0b1494a934..7cae355e3490 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -145,11 +145,6 @@ static inline bool vmx_umip_emulated(void)
 		SECONDARY_EXEC_DESC;
 }
 
-static inline bool vmx_pku_supported(void)
-{
-	return boot_cpu_has(X86_FEATURE_PKU);
-}
-
 static inline bool cpu_has_vmx_rdtscp(void)
 {
 	return vmcs_config.cpu_based_2nd_exec_ctrl &
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 6bcdfb8744d3..3845ca7da6e0 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7900,7 +7900,6 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = {
 	.xsaves_supported = vmx_xsaves_supported,
 	.umip_emulated = vmx_umip_emulated,
 	.pt_supported = vmx_pt_supported,
-	.pku_supported = vmx_pku_supported,
 
 	.request_immediate_exit = vmx_request_immediate_exit,
 
-- 
2.24.1