[PATCH 1/4] KVM: x86: Add a struct to consolidate host values, e.g. EFER, XCR0, etc...
From: Sean Christopherson
Date: Tue Apr 23 2024 - 18:15:52 EST
Add "struct kvm_host_values kvm_host" to hold the various host values
that KVM snapshots during initialization. Bundling the host values into
a single struct simplifies adding new MSRs and other features with host
state/values that KVM cares about, and provides a one-stop shop. E.g.
adding a new value requires one line, whereas tracking each value
individual often requires three: declaration, definition, and export.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 1 -
arch/x86/kvm/svm/sev.c | 2 +-
arch/x86/kvm/vmx/nested.c | 8 +++----
arch/x86/kvm/vmx/vmx.c | 14 ++++++------
arch/x86/kvm/x86.c | 38 +++++++++++++--------------------
arch/x86/kvm/x86.h | 12 +++++++----
6 files changed, 35 insertions(+), 40 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 1d13e3cd1dc5..8d3940a59894 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1846,7 +1846,6 @@ struct kvm_arch_async_pf {
};
extern u32 __read_mostly kvm_nr_uret_msrs;
-extern u64 __read_mostly host_efer;
extern bool __read_mostly allow_smaller_maxphyaddr;
extern bool __read_mostly enable_apicv;
extern struct kvm_x86_ops kvm_x86_ops;
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 598d78b4107f..71f1518f0ca1 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3251,7 +3251,7 @@ void sev_es_prepare_switch_to_guest(struct vcpu_svm *svm, struct sev_es_save_are
*/
hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
hostsa->pkru = read_pkru();
- hostsa->xss = host_xss;
+ hostsa->xss = kvm_host.xss;
/*
* If DebugSwap is enabled, debug registers are loaded but NOT saved by
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index d5b832126e34..a896df59eaad 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2422,7 +2422,7 @@ static void prepare_vmcs02_early(struct vcpu_vmx *vmx, struct loaded_vmcs *vmcs0
if (cpu_has_load_ia32_efer()) {
if (guest_efer & EFER_LMA)
exec_control |= VM_ENTRY_IA32E_MODE;
- if (guest_efer != host_efer)
+ if (guest_efer != kvm_host.efer)
exec_control |= VM_ENTRY_LOAD_IA32_EFER;
}
vm_entry_controls_set(vmx, exec_control);
@@ -2435,7 +2435,7 @@ static void prepare_vmcs02_early(struct vcpu_vmx *vmx, struct loaded_vmcs *vmcs0
* bits may be modified by vmx_set_efer() in prepare_vmcs02().
*/
exec_control = __vm_exit_controls_get(vmcs01);
- if (cpu_has_load_ia32_efer() && guest_efer != host_efer)
+ if (cpu_has_load_ia32_efer() && guest_efer != kvm_host.efer)
exec_control |= VM_EXIT_LOAD_IA32_EFER;
else
exec_control &= ~VM_EXIT_LOAD_IA32_EFER;
@@ -4662,7 +4662,7 @@ static inline u64 nested_vmx_get_vmcs01_guest_efer(struct vcpu_vmx *vmx)
return vmcs_read64(GUEST_IA32_EFER);
if (cpu_has_load_ia32_efer())
- return host_efer;
+ return kvm_host.efer;
for (i = 0; i < vmx->msr_autoload.guest.nr; ++i) {
if (vmx->msr_autoload.guest.val[i].index == MSR_EFER)
@@ -4673,7 +4673,7 @@ static inline u64 nested_vmx_get_vmcs01_guest_efer(struct vcpu_vmx *vmx)
if (efer_msr)
return efer_msr->data;
- return host_efer;
+ return kvm_host.efer;
}
static void nested_vmx_restore_host_state(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index f10b5f8f364b..cb1bd9aebac4 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -258,7 +258,7 @@ static int vmx_setup_l1d_flush(enum vmx_l1d_flush_state l1tf)
return 0;
}
- if (host_arch_capabilities & ARCH_CAP_SKIP_VMENTRY_L1DFLUSH) {
+ if (kvm_host.arch_capabilities & ARCH_CAP_SKIP_VMENTRY_L1DFLUSH) {
l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_NOT_REQUIRED;
return 0;
}
@@ -403,7 +403,7 @@ static void vmx_update_fb_clear_dis(struct kvm_vcpu *vcpu, struct vcpu_vmx *vmx)
* and VM-Exit.
*/
vmx->disable_fb_clear = !cpu_feature_enabled(X86_FEATURE_CLEAR_CPU_BUF) &&
- (host_arch_capabilities & ARCH_CAP_FB_CLEAR_CTRL) &&
+ (kvm_host.arch_capabilities & ARCH_CAP_FB_CLEAR_CTRL) &&
!boot_cpu_has_bug(X86_BUG_MDS) &&
!boot_cpu_has_bug(X86_BUG_TAA);
@@ -1116,12 +1116,12 @@ static bool update_transition_efer(struct vcpu_vmx *vmx)
* atomically, since it's faster than switching it manually.
*/
if (cpu_has_load_ia32_efer() ||
- (enable_ept && ((vmx->vcpu.arch.efer ^ host_efer) & EFER_NX))) {
+ (enable_ept && ((vmx->vcpu.arch.efer ^ kvm_host.efer) & EFER_NX))) {
if (!(guest_efer & EFER_LMA))
guest_efer &= ~EFER_LME;
- if (guest_efer != host_efer)
+ if (guest_efer != kvm_host.efer)
add_atomic_switch_msr(vmx, MSR_EFER,
- guest_efer, host_efer, false);
+ guest_efer, kvm_host.efer, false);
else
clear_atomic_switch_msr(vmx, MSR_EFER);
return false;
@@ -1134,7 +1134,7 @@ static bool update_transition_efer(struct vcpu_vmx *vmx)
clear_atomic_switch_msr(vmx, MSR_EFER);
guest_efer &= ~ignore_bits;
- guest_efer |= host_efer & ignore_bits;
+ guest_efer |= kvm_host.efer & ignore_bits;
vmx->guest_uret_msrs[i].data = guest_efer;
vmx->guest_uret_msrs[i].mask = ~ignore_bits;
@@ -4346,7 +4346,7 @@ void vmx_set_constant_host_state(struct vcpu_vmx *vmx)
}
if (cpu_has_load_ia32_efer())
- vmcs_write64(HOST_IA32_EFER, host_efer);
+ vmcs_write64(HOST_IA32_EFER, kvm_host.efer);
}
void set_cr4_guest_host_mask(struct vcpu_vmx *vmx)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e9ef1fa4b90b..1b664385461d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -98,6 +98,9 @@ struct kvm_caps kvm_caps __read_mostly = {
};
EXPORT_SYMBOL_GPL(kvm_caps);
+struct kvm_host_values kvm_host __read_mostly;
+EXPORT_SYMBOL_GPL(kvm_host);
+
#define ERR_PTR_USR(e) ((void __user *)ERR_PTR(e))
#define emul_to_vcpu(ctxt) \
@@ -227,21 +230,12 @@ static struct kvm_user_return_msrs __percpu *user_return_msrs;
| XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \
| XFEATURE_MASK_PKRU | XFEATURE_MASK_XTILE)
-u64 __read_mostly host_efer;
-EXPORT_SYMBOL_GPL(host_efer);
-
bool __read_mostly allow_smaller_maxphyaddr = 0;
EXPORT_SYMBOL_GPL(allow_smaller_maxphyaddr);
bool __read_mostly enable_apicv = true;
EXPORT_SYMBOL_GPL(enable_apicv);
-u64 __read_mostly host_xss;
-EXPORT_SYMBOL_GPL(host_xss);
-
-u64 __read_mostly host_arch_capabilities;
-EXPORT_SYMBOL_GPL(host_arch_capabilities);
-
const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
KVM_GENERIC_VM_STATS(),
STATS_DESC_COUNTER(VM, mmu_shadow_zapped),
@@ -315,8 +309,6 @@ const struct kvm_stats_header kvm_vcpu_stats_header = {
sizeof(kvm_vcpu_stats_desc),
};
-u64 __read_mostly host_xcr0;
-
static struct kmem_cache *x86_emulator_cache;
/*
@@ -1023,11 +1015,11 @@ void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu)
if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) {
- if (vcpu->arch.xcr0 != host_xcr0)
+ if (vcpu->arch.xcr0 != kvm_host.xcr0)
xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0);
if (guest_can_use(vcpu, X86_FEATURE_XSAVES) &&
- vcpu->arch.ia32_xss != host_xss)
+ vcpu->arch.ia32_xss != kvm_host.xss)
wrmsrl(MSR_IA32_XSS, vcpu->arch.ia32_xss);
}
@@ -1054,12 +1046,12 @@ void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu)
if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) {
- if (vcpu->arch.xcr0 != host_xcr0)
- xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0);
+ if (vcpu->arch.xcr0 != kvm_host.xcr0)
+ xsetbv(XCR_XFEATURE_ENABLED_MASK, kvm_host.xcr0);
if (guest_can_use(vcpu, X86_FEATURE_XSAVES) &&
- vcpu->arch.ia32_xss != host_xss)
- wrmsrl(MSR_IA32_XSS, host_xss);
+ vcpu->arch.ia32_xss != kvm_host.xss)
+ wrmsrl(MSR_IA32_XSS, kvm_host.xss);
}
}
@@ -1626,7 +1618,7 @@ static bool kvm_is_immutable_feature_msr(u32 msr)
static u64 kvm_get_arch_capabilities(void)
{
- u64 data = host_arch_capabilities & KVM_SUPPORTED_ARCH_CAP;
+ u64 data = kvm_host.arch_capabilities & KVM_SUPPORTED_ARCH_CAP;
/*
* If nx_huge_pages is enabled, KVM's shadow paging will ensure that
@@ -9777,19 +9769,19 @@ int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
goto out_free_percpu;
if (boot_cpu_has(X86_FEATURE_XSAVE)) {
- host_xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
- kvm_caps.supported_xcr0 = host_xcr0 & KVM_SUPPORTED_XCR0;
+ kvm_host.xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
+ kvm_caps.supported_xcr0 = kvm_host.xcr0 & KVM_SUPPORTED_XCR0;
}
- rdmsrl_safe(MSR_EFER, &host_efer);
+ rdmsrl_safe(MSR_EFER, &kvm_host.efer);
if (boot_cpu_has(X86_FEATURE_XSAVES))
- rdmsrl(MSR_IA32_XSS, host_xss);
+ rdmsrl(MSR_IA32_XSS, kvm_host.xss);
kvm_init_pmu_capability(ops->pmu_ops);
if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES))
- rdmsrl(MSR_IA32_ARCH_CAPABILITIES, host_arch_capabilities);
+ rdmsrl(MSR_IA32_ARCH_CAPABILITIES, kvm_host.arch_capabilities);
r = ops->hardware_setup();
if (r != 0)
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index d80a4c6b5a38..e69fff7d1f21 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -33,6 +33,13 @@ struct kvm_caps {
u64 supported_perf_cap;
};
+struct kvm_host_values {
+ u64 efer;
+ u64 xcr0;
+ u64 xss;
+ u64 arch_capabilities;
+};
+
void kvm_spurious_fault(void);
#define KVM_NESTED_VMENTER_CONSISTENCY_CHECK(consistency_check) \
@@ -325,11 +332,8 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
int emulation_type, void *insn, int insn_len);
fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu);
-extern u64 host_xcr0;
-extern u64 host_xss;
-extern u64 host_arch_capabilities;
-
extern struct kvm_caps kvm_caps;
+extern struct kvm_host_values kvm_host;
extern bool enable_pmu;
--
2.44.0.769.g3c40516874-goog