diff options
| -rw-r--r-- | arch/x86/kvm/x86.c | 61 |
1 files changed, 43 insertions, 18 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index f0288c52d5e4..6f9cab071eca 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4751,25 +4751,25 @@ static int handle_emulation_failure(struct kvm_vcpu *vcpu) return r; } -static bool reexecute_instruction(struct kvm_vcpu *vcpu, gva_t gva) +static bool reexecute_instruction(struct kvm_vcpu *vcpu, gva_t cr2) { - gpa_t gpa; + gpa_t gpa = cr2; pfn_t pfn; - if (tdp_enabled) - return false; - - gpa = kvm_mmu_gva_to_gpa_system(vcpu, gva, NULL); - if (gpa == UNMAPPED_GVA) - return true; /* let cpu generate fault */ + if (!vcpu->arch.mmu.direct_map) { + /* + * Write permission should be allowed since only + * write access need to be emulated. + */ + gpa = kvm_mmu_gva_to_gpa_write(vcpu, cr2, NULL); - /* - * if emulation was due to access to shadowed page table - * and it failed try to unshadow page and re-enter the - * guest to let CPU execute the instruction. - */ - if (kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa))) - return true; + /* + * If the mapping is invalid in guest, let cpu retry + * it to generate fault. + */ + if (gpa == UNMAPPED_GVA) + return true; + } /* * Do not retry the unhandleable instruction if it faults on the @@ -4778,12 +4778,37 @@ static bool reexecute_instruction(struct kvm_vcpu *vcpu, gva_t gva) * instruction -> ... */ pfn = gfn_to_pfn(vcpu->kvm, gpa_to_gfn(gpa)); - if (!is_error_noslot_pfn(pfn)) { - kvm_release_pfn_clean(pfn); + + /* + * If the instruction failed on the error pfn, it can not be fixed, + * report the error to userspace. + */ + if (is_error_noslot_pfn(pfn)) + return false; + + kvm_release_pfn_clean(pfn); + + /* The instructions are well-emulated on direct mmu. */ + if (vcpu->arch.mmu.direct_map) { + unsigned int indirect_shadow_pages; + + spin_lock(&vcpu->kvm->mmu_lock); + indirect_shadow_pages = vcpu->kvm->arch.indirect_shadow_pages; + spin_unlock(&vcpu->kvm->mmu_lock); + + if (indirect_shadow_pages) + kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa)); + return true; } - return false; + /* + * if emulation was due to access to shadowed page table + * and it failed try to unshadow page and re-enter the + * guest to let CPU execute the instruction. + */ + kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa)); + return true; } static bool retry_instruction(struct x86_emulate_ctxt *ctxt, |