From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Maxim Levitsky Date: Tue, 21 Jun 2022 18:09:01 +0300 Subject: [PATCH] KVM: x86: SVM: use smram structs This removes the last user of put_smstate/GET_SMSTATE so remove these functions as well. Also add a sanity check that we don't attempt to enter the SMM on non long mode capable guest CPU with a running nested guest. Signed-off-by: Maxim Levitsky Signed-off-by: Thomas Lamprecht --- arch/x86/include/asm/kvm_host.h | 6 ------ arch/x86/kvm/svm/svm.c | 28 +++++++++++++++++----------- 2 files changed, 17 insertions(+), 17 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 9217bd6cf0d1..7d9fd7dcbacd 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -2041,12 +2041,6 @@ static inline int kvm_cpu_get_apicid(int mps_cpu) #endif } -#define put_smstate(type, buf, offset, val) \ - *(type *)((buf) + (offset) - 0x7e00) = val - -#define GET_SMSTATE(type, buf, offset) \ - (*(type *)((buf) + (offset) - 0x7e00)) - int kvm_cpu_dirty_log_size(void); int memslot_rmap_alloc(struct kvm_memory_slot *slot, unsigned long npages); diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 44bbf25dfeb9..e26084734c1b 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -4301,6 +4301,7 @@ static int svm_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection) static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate) { + struct kvm_smram_state_64 *smram = (struct kvm_smram_state_64 *)smstate; struct vcpu_svm *svm = to_svm(vcpu); struct kvm_host_map map_save; int ret; @@ -4308,10 +4309,17 @@ static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate) if (!is_guest_mode(vcpu)) return 0; - /* FED8h - SVM Guest */ - put_smstate(u64, smstate, 0x7ed8, 1); - /* FEE0h - SVM Guest VMCB Physical Address */ - put_smstate(u64, smstate, 0x7ee0, svm->nested.vmcb12_gpa); + /* + * 32 bit SMRAM format doesn't preserve EFER and SVM state. + * SVM should not be enabled by the userspace without marking + * the CPU as at least long mode capable. + */ + + if (!guest_cpuid_has(vcpu, X86_FEATURE_SVM)) + return 1; + + smram->svm_guest_flag = 1; + smram->svm_guest_vmcb_gpa = svm->nested.vmcb12_gpa; svm->vmcb->save.rax = vcpu->arch.regs[VCPU_REGS_RAX]; svm->vmcb->save.rsp = vcpu->arch.regs[VCPU_REGS_RSP]; @@ -4348,9 +4356,9 @@ static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate) static int svm_leave_smm(struct kvm_vcpu *vcpu, const char *smstate) { + struct kvm_smram_state_64 *smram = (struct kvm_smram_state_64 *)smstate; struct vcpu_svm *svm = to_svm(vcpu); struct kvm_host_map map, map_save; - u64 saved_efer, vmcb12_gpa; struct vmcb *vmcb12; int ret; @@ -4358,18 +4366,16 @@ static int svm_leave_smm(struct kvm_vcpu *vcpu, const char *smstate) return 0; /* Non-zero if SMI arrived while vCPU was in guest mode. */ - if (!GET_SMSTATE(u64, smstate, 0x7ed8)) + if (!smram->svm_guest_flag) return 0; if (!guest_cpuid_has(vcpu, X86_FEATURE_SVM)) return 1; - saved_efer = GET_SMSTATE(u64, smstate, 0x7ed0); - if (!(saved_efer & EFER_SVME)) + if (!(smram->efer & EFER_SVME)) return 1; - vmcb12_gpa = GET_SMSTATE(u64, smstate, 0x7ee0); - if (kvm_vcpu_map(vcpu, gpa_to_gfn(vmcb12_gpa), &map) == -EINVAL) + if (kvm_vcpu_map(vcpu, gpa_to_gfn(smram->svm_guest_vmcb_gpa), &map) == -EINVAL) return 1; ret = 1; @@ -4395,7 +4401,7 @@ static int svm_leave_smm(struct kvm_vcpu *vcpu, const char *smstate) vmcb12 = map.hva; nested_copy_vmcb_control_to_cache(svm, &vmcb12->control); nested_copy_vmcb_save_to_cache(svm, &vmcb12->save); - ret = enter_svm_guest_mode(vcpu, vmcb12_gpa, vmcb12, false); + ret = enter_svm_guest_mode(vcpu, smram->svm_guest_vmcb_gpa, vmcb12, false); if (ret) goto unmap_save;