diff options
| -rw-r--r-- | arch/x86/kvm/mmu.c | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 80fc5bd4a32a..ea744cc0d3fc 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -281,6 +281,11 @@ static const u64 shadow_nonpresent_or_rsvd_mask_len = 5; */ static u64 __read_mostly shadow_nonpresent_or_rsvd_lower_gfn_mask; +/* + * The number of non-reserved physical address bits irrespective of features + * that repurpose legal bits, e.g. MKTME. + */ +static u8 __read_mostly shadow_phys_bits; static void mmu_spte_set(u64 *sptep, u64 spte); static bool is_executable_pte(u64 spte); @@ -464,6 +469,21 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, } EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes); +static u8 kvm_get_shadow_phys_bits(void) +{ + /* + * boot_cpu_data.x86_phys_bits is reduced when MKTME is detected + * in CPU detection code, but MKTME treats those reduced bits as + * 'keyID' thus they are not reserved bits. Therefore for MKTME + * we should still return physical address bits reported by CPUID. + */ + if (!boot_cpu_has(X86_FEATURE_TME) || + WARN_ON_ONCE(boot_cpu_data.extended_cpuid_level < 0x80000008)) + return boot_cpu_data.x86_phys_bits; + + return cpuid_eax(0x80000008) & 0xff; +} + static void kvm_mmu_reset_all_pte_masks(void) { u8 low_phys_bits; @@ -477,6 +497,8 @@ static void kvm_mmu_reset_all_pte_masks(void) shadow_present_mask = 0; shadow_acc_track_mask = 0; + shadow_phys_bits = kvm_get_shadow_phys_bits(); + /* * If the CPU has 46 or less physical address bits, then set an * appropriate mask to guard against L1TF attacks. Otherwise, it is @@ -4544,7 +4566,7 @@ reset_shadow_zero_bits_mask(struct kvm_vcpu *vcpu, struct kvm_mmu *context) */ shadow_zero_check = &context->shadow_zero_check; __reset_rsvds_bits_mask(vcpu, shadow_zero_check, - boot_cpu_data.x86_phys_bits, + shadow_phys_bits, context->shadow_root_level, uses_nx, guest_cpuid_has(vcpu, X86_FEATURE_GBPAGES), is_pse(vcpu), true); @@ -4581,13 +4603,13 @@ reset_tdp_shadow_zero_bits_mask(struct kvm_vcpu *vcpu, if (boot_cpu_is_amd()) __reset_rsvds_bits_mask(vcpu, shadow_zero_check, - boot_cpu_data.x86_phys_bits, + shadow_phys_bits, context->shadow_root_level, false, boot_cpu_has(X86_FEATURE_GBPAGES), true, true); else __reset_rsvds_bits_mask_ept(shadow_zero_check, - boot_cpu_data.x86_phys_bits, + shadow_phys_bits, false); if (!shadow_me_mask) @@ -4608,7 +4630,7 @@ reset_ept_shadow_zero_bits_mask(struct kvm_vcpu *vcpu, struct kvm_mmu *context, bool execonly) { __reset_rsvds_bits_mask_ept(&context->shadow_zero_check, - boot_cpu_data.x86_phys_bits, execonly); + shadow_phys_bits, execonly); } #define BYTE_MASK(access) \ @@ -6053,7 +6075,6 @@ static int set_nx_huge_pages(const char *val, const struct kernel_param *kp) static void kvm_set_mmio_spte_mask(void) { u64 mask; - int maxphyaddr = boot_cpu_data.x86_phys_bits; /* * Set the reserved bits and the present bit of an paging-structure @@ -6073,7 +6094,7 @@ static void kvm_set_mmio_spte_mask(void) * If reserved bit is not supported, clear the present bit to disable * mmio page fault. */ - if (maxphyaddr == 52) + if (shadow_phys_bits == 52) mask &= ~1ull; kvm_mmu_set_mmio_spte_mask(mask, mask); |