Add a helper to generate the mask of reserved GPA bits _without_ any adjustments for repurposed bits, and use it to replace a variety of open coded variants in the MTRR and APIC_BASE flows.
No functional change intended. Signed-off-by: Sean Christopherson <[email protected]> --- arch/x86/kvm/cpuid.c | 12 +++++++++++- arch/x86/kvm/cpuid.h | 1 + arch/x86/kvm/mtrr.c | 12 ++++++------ arch/x86/kvm/x86.c | 4 ++-- 4 files changed, 20 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index d313b1804278..dd9406450696 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -188,7 +188,7 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) kvm_update_pv_runtime(vcpu); vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu); - vcpu->arch.reserved_gpa_bits = rsvd_bits(cpuid_maxphyaddr(vcpu), 63); + vcpu->arch.reserved_gpa_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu); kvm_pmu_refresh(vcpu); vcpu->arch.cr4_guest_rsvd_bits = @@ -242,6 +242,16 @@ int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu) return 36; } +/* + * This "raw" version returns the reserved GPA bits without any adjustments for + * encryption technologies that usurp bits. The raw mask should be used if and + * only if hardware does _not_ strip the usurped bits, e.g. in virtual MTRRs. + */ +u64 kvm_vcpu_reserved_gpa_bits_raw(struct kvm_vcpu *vcpu) +{ + return rsvd_bits(cpuid_maxphyaddr(vcpu), 63); +} + /* when an old userspace process fills a new kernel module */ int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid *cpuid, diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index f673f45bdf52..2a0c5064497f 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -30,6 +30,7 @@ bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, bool exact_only); int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu); +u64 kvm_vcpu_reserved_gpa_bits_raw(struct kvm_vcpu *vcpu); static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu) { diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c index f472fdb6ae7e..a8502e02f479 100644 --- a/arch/x86/kvm/mtrr.c +++ b/arch/x86/kvm/mtrr.c @@ -75,7 +75,7 @@ bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data) /* variable MTRRs */ WARN_ON(!(msr >= 0x200 && msr < 0x200 + 2 * KVM_NR_VAR_MTRR)); - mask = (~0ULL) << cpuid_maxphyaddr(vcpu); + mask = kvm_vcpu_reserved_gpa_bits_raw(vcpu); if ((msr & 1) == 0) { /* MTRR base */ if (!valid_mtrr_type(data & 0xff)) @@ -351,14 +351,14 @@ static void set_var_mtrr_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data) if (var_mtrr_range_is_valid(cur)) list_del(&mtrr_state->var_ranges[index].node); - /* Extend the mask with all 1 bits to the left, since those - * bits must implicitly be 0. The bits are then cleared - * when reading them. + /* + * Set all illegal GPA bits in the mask, since those bits must + * implicitly be 0. The bits are then cleared when reading them. */ if (!is_mtrr_mask) cur->base = data; else - cur->mask = data | (-1LL << cpuid_maxphyaddr(vcpu)); + cur->mask = data | kvm_vcpu_reserved_gpa_bits_raw(vcpu); /* add it to the list if it's enabled. */ if (var_mtrr_range_is_valid(cur)) { @@ -426,7 +426,7 @@ int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata) else *pdata = vcpu->arch.mtrr_state.var_ranges[index].mask; - *pdata &= (1ULL << cpuid_maxphyaddr(vcpu)) - 1; + *pdata &= ~kvm_vcpu_reserved_gpa_bits_raw(vcpu); } return 0; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 82a70511c0d3..28fea7ff7a86 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -408,7 +408,7 @@ int kvm_set_apic_base(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { enum lapic_mode old_mode = kvm_get_apic_mode(vcpu); enum lapic_mode new_mode = kvm_apic_mode(msr_info->data); - u64 reserved_bits = ((~0ULL) << cpuid_maxphyaddr(vcpu)) | 0x2ff | + u64 reserved_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu) | 0x2ff | (guest_cpuid_has(vcpu, X86_FEATURE_X2APIC) ? 0 : X2APIC_ENABLE); if ((msr_info->data & reserved_bits) != 0 || new_mode == LAPIC_MODE_INVALID) @@ -10089,7 +10089,7 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) fx_init(vcpu); vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu); - vcpu->arch.reserved_gpa_bits = rsvd_bits(cpuid_maxphyaddr(vcpu), 63); + vcpu->arch.reserved_gpa_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu); vcpu->arch.pat = MSR_IA32_CR_PAT_DEFAULT; -- 2.30.0.365.g02bc693789-goog
