From: Sean Christopherson <[email protected]> Extract the logic for emulating CPUID faulting (where CPUID #GPs at CPL>0 outside of SMM) into a dedicated helper and use the helper for both the full emulator and the intercepted-CPUID paths.
Opportunistically drop kvm_require_cpl(), as kvm_emulate_cpuid() was the one and only user. No functional change intended. Signed-off-by: Sean Christopherson <[email protected]> [jim: Add EXPORT_STATIC_CALL_GPL(kvm_x86_get_cpl) so that KVM vendor modules can call kvm_is_cpuid_allowed(). Fix typo in commit message.] Signed-off-by: Jim Mattson <[email protected]> Reviewed-by: Binbin Wu <[email protected]> --- arch/x86/include/asm/kvm_host.h | 1 - arch/x86/kvm/cpuid.c | 5 +++-- arch/x86/kvm/cpuid.h | 8 ++++++++ arch/x86/kvm/emulate.c | 6 +----- arch/x86/kvm/kvm_emulate.h | 1 + arch/x86/kvm/x86.c | 19 +++++++------------ 6 files changed, 20 insertions(+), 20 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index d72051150bac..4c22b338ac7b 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -2321,7 +2321,6 @@ static inline void kvm_inject_emulated_page_fault(struct kvm_vcpu *vcpu, __kvm_inject_emulated_page_fault(vcpu, fault, false); } -bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl); bool kvm_require_dr(struct kvm_vcpu *vcpu, int dr); static inline int __kvm_irq_line_state(unsigned long *irq_state, diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index e69156b54cff..1c95d1fa3ead 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -2161,9 +2161,10 @@ int kvm_emulate_cpuid(struct kvm_vcpu *vcpu) { u32 eax, ebx, ecx, edx; - if (!is_smm(vcpu) && cpuid_fault_enabled(vcpu) && - !kvm_require_cpl(vcpu, 0)) + if (!kvm_is_cpuid_allowed(vcpu)) { + kvm_queue_exception_e(vcpu, GP_VECTOR, 0); return 1; + } eax = kvm_rax_read(vcpu); ecx = kvm_rcx_read(vcpu); diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index 039b8e6f40ba..bc4a8428b836 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -7,6 +7,8 @@ #include <asm/processor.h> #include <uapi/asm/kvm_para.h> +#include "smm.h" + extern u32 kvm_cpu_caps[NR_KVM_CPU_CAPS] __read_mostly; extern bool kvm_is_configuring_cpu_caps __read_mostly; @@ -192,6 +194,12 @@ static inline bool cpuid_fault_enabled(struct kvm_vcpu *vcpu) MSR_MISC_FEATURES_ENABLES_CPUID_FAULT; } +static inline bool kvm_is_cpuid_allowed(struct kvm_vcpu *vcpu) +{ + return !cpuid_fault_enabled(vcpu) || is_smm(vcpu) || + !kvm_x86_call(get_cpl)(vcpu); +} + static __always_inline void kvm_cpu_cap_clear(unsigned int x86_feature) { unsigned int x86_leaf = __feature_leaf(x86_feature); diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 0a17a9ee6f32..585a8ceab220 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3594,12 +3594,8 @@ static int em_sti(struct x86_emulate_ctxt *ctxt) static int em_cpuid(struct x86_emulate_ctxt *ctxt) { u32 eax, ebx, ecx, edx; - u64 msr = 0; - ctxt->ops->get_msr(ctxt, MSR_MISC_FEATURES_ENABLES, &msr); - if (!ctxt->ops->is_smm(ctxt) && - (msr & MSR_MISC_FEATURES_ENABLES_CPUID_FAULT) && - ctxt->ops->cpl(ctxt)) + if (!ctxt->ops->is_cpuid_allowed(ctxt)) return emulate_gp(ctxt, 0); eax = reg_read(ctxt, VCPU_REGS_RAX); diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h index f5df31a52996..3e375af15c03 100644 --- a/arch/x86/kvm/kvm_emulate.h +++ b/arch/x86/kvm/kvm_emulate.h @@ -230,6 +230,7 @@ struct x86_emulate_ops { struct x86_instruction_info *info, enum x86_intercept_stage stage); + bool (*is_cpuid_allowed)(struct x86_emulate_ctxt *ctxt); bool (*get_cpuid)(struct x86_emulate_ctxt *ctxt, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, bool exact_only); bool (*guest_has_movbe)(struct x86_emulate_ctxt *ctxt); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 1578c0ecbbd1..72bd3cddb026 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -151,6 +151,7 @@ struct kvm_x86_ops kvm_x86_ops __read_mostly; #include <asm/kvm-x86-ops.h> EXPORT_STATIC_CALL_GPL(kvm_x86_get_cs_db_l_bits); EXPORT_STATIC_CALL_GPL(kvm_x86_cache_reg); +EXPORT_STATIC_CALL_GPL(kvm_x86_get_cpl); static bool __read_mostly ignore_msrs = 0; module_param(ignore_msrs, bool, 0644); @@ -1022,18 +1023,6 @@ void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code) } EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_queue_exception_e); -/* - * Checks if cpl <= required_cpl; if true, return true. Otherwise queue - * a #GP and return false. - */ -bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl) -{ - if (kvm_x86_call(get_cpl)(vcpu) <= required_cpl) - return true; - kvm_queue_exception_e(vcpu, GP_VECTOR, 0); - return false; -} - bool kvm_require_dr(struct kvm_vcpu *vcpu, int dr) { if ((dr != 4 && dr != 5) || !kvm_is_cr4_bit_set(vcpu, X86_CR4_DE)) @@ -8829,6 +8818,11 @@ static int emulator_intercept(struct x86_emulate_ctxt *ctxt, &ctxt->exception); } +static bool emulator_is_cpuid_allowed(struct x86_emulate_ctxt *ctxt) +{ + return kvm_is_cpuid_allowed(emul_to_vcpu(ctxt)); +} + static bool emulator_get_cpuid(struct x86_emulate_ctxt *ctxt, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, bool exact_only) @@ -8966,6 +8960,7 @@ static const struct x86_emulate_ops emulate_ops = { .wbinvd = emulator_wbinvd, .fix_hypercall = emulator_fix_hypercall, .intercept = emulator_intercept, + .is_cpuid_allowed = emulator_is_cpuid_allowed, .get_cpuid = emulator_get_cpuid, .guest_has_movbe = emulator_guest_has_movbe, .guest_has_fxsr = emulator_guest_has_fxsr, -- 2.54.0.794.g4f17f83d09-goog
