KVM: SEV: snapshot the GHCB before accessing it

[platform/kernel/linux-starfive.git] / arch / x86 / kvm / svm / sev.c

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 4cb2e48..38fbe9d 100644 (file)
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -2410,15 +2410,18 @@ static void sev_es_sync_from_ghcb(struct vcpu_svm *svm)
         */
        memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs));
 
-       vcpu->arch.regs[VCPU_REGS_RAX] = ghcb_get_rax_if_valid(ghcb);
-       vcpu->arch.regs[VCPU_REGS_RBX] = ghcb_get_rbx_if_valid(ghcb);
-       vcpu->arch.regs[VCPU_REGS_RCX] = ghcb_get_rcx_if_valid(ghcb);
-       vcpu->arch.regs[VCPU_REGS_RDX] = ghcb_get_rdx_if_valid(ghcb);
-       vcpu->arch.regs[VCPU_REGS_RSI] = ghcb_get_rsi_if_valid(ghcb);
+       BUILD_BUG_ON(sizeof(svm->sev_es.valid_bitmap) != sizeof(ghcb->save.valid_bitmap));
+       memcpy(&svm->sev_es.valid_bitmap, &ghcb->save.valid_bitmap, sizeof(ghcb->save.valid_bitmap));
 
-       svm->vmcb->save.cpl = ghcb_get_cpl_if_valid(ghcb);
+       vcpu->arch.regs[VCPU_REGS_RAX] = kvm_ghcb_get_rax_if_valid(svm, ghcb);
+       vcpu->arch.regs[VCPU_REGS_RBX] = kvm_ghcb_get_rbx_if_valid(svm, ghcb);
+       vcpu->arch.regs[VCPU_REGS_RCX] = kvm_ghcb_get_rcx_if_valid(svm, ghcb);
+       vcpu->arch.regs[VCPU_REGS_RDX] = kvm_ghcb_get_rdx_if_valid(svm, ghcb);
+       vcpu->arch.regs[VCPU_REGS_RSI] = kvm_ghcb_get_rsi_if_valid(svm, ghcb);
 
-       if (ghcb_xcr0_is_valid(ghcb)) {
+       svm->vmcb->save.cpl = kvm_ghcb_get_cpl_if_valid(svm, ghcb);
+
+       if (kvm_ghcb_xcr0_is_valid(svm)) {
                vcpu->arch.xcr0 = ghcb_get_xcr0(ghcb);
                kvm_update_cpuid_runtime(vcpu);
        }
@@ -2429,6 +2432,7 @@ static void sev_es_sync_from_ghcb(struct vcpu_svm *svm)
        control->exit_code_hi = upper_32_bits(exit_code);
        control->exit_info_1 = ghcb_get_sw_exit_info_1(ghcb);
        control->exit_info_2 = ghcb_get_sw_exit_info_2(ghcb);
+       svm->sev_es.sw_scratch = kvm_ghcb_get_sw_scratch_if_valid(svm, ghcb);
 
        /* Clear the valid entries fields */
        memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap));
@@ -2457,56 +2461,56 @@ static int sev_es_validate_vmgexit(struct vcpu_svm *svm)
 
        reason = GHCB_ERR_MISSING_INPUT;
 
-       if (!ghcb_sw_exit_code_is_valid(ghcb) ||
-           !ghcb_sw_exit_info_1_is_valid(ghcb) ||
-           !ghcb_sw_exit_info_2_is_valid(ghcb))
+       if (!kvm_ghcb_sw_exit_code_is_valid(svm) ||
+           !kvm_ghcb_sw_exit_info_1_is_valid(svm) ||
+           !kvm_ghcb_sw_exit_info_2_is_valid(svm))
                goto vmgexit_err;
 
        switch (ghcb_get_sw_exit_code(ghcb)) {
        case SVM_EXIT_READ_DR7:
                break;
        case SVM_EXIT_WRITE_DR7:
-               if (!ghcb_rax_is_valid(ghcb))
+               if (!kvm_ghcb_rax_is_valid(svm))
                        goto vmgexit_err;
                break;
        case SVM_EXIT_RDTSC:
                break;
        case SVM_EXIT_RDPMC:
-               if (!ghcb_rcx_is_valid(ghcb))
+               if (!kvm_ghcb_rcx_is_valid(svm))
                        goto vmgexit_err;
                break;
        case SVM_EXIT_CPUID:
-               if (!ghcb_rax_is_valid(ghcb) ||
-                   !ghcb_rcx_is_valid(ghcb))
+               if (!kvm_ghcb_rax_is_valid(svm) ||
+                   !kvm_ghcb_rcx_is_valid(svm))
                        goto vmgexit_err;
                if (ghcb_get_rax(ghcb) == 0xd)
-                       if (!ghcb_xcr0_is_valid(ghcb))
+                       if (!kvm_ghcb_xcr0_is_valid(svm))
                                goto vmgexit_err;
                break;
        case SVM_EXIT_INVD:
                break;
        case SVM_EXIT_IOIO:
                if (ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_STR_MASK) {
-                       if (!ghcb_sw_scratch_is_valid(ghcb))
+                       if (!kvm_ghcb_sw_scratch_is_valid(svm))
                                goto vmgexit_err;
                } else {
                        if (!(ghcb_get_sw_exit_info_1(ghcb) & SVM_IOIO_TYPE_MASK))
-                               if (!ghcb_rax_is_valid(ghcb))
+                               if (!kvm_ghcb_rax_is_valid(svm))
                                        goto vmgexit_err;
                }
                break;
        case SVM_EXIT_MSR:
-               if (!ghcb_rcx_is_valid(ghcb))
+               if (!kvm_ghcb_rcx_is_valid(svm))
                        goto vmgexit_err;
                if (ghcb_get_sw_exit_info_1(ghcb)) {
-                       if (!ghcb_rax_is_valid(ghcb) ||
-                           !ghcb_rdx_is_valid(ghcb))
+                       if (!kvm_ghcb_rax_is_valid(svm) ||
+                           !kvm_ghcb_rdx_is_valid(svm))
                                goto vmgexit_err;
                }
                break;
        case SVM_EXIT_VMMCALL:
-               if (!ghcb_rax_is_valid(ghcb) ||
-                   !ghcb_cpl_is_valid(ghcb))
+               if (!kvm_ghcb_rax_is_valid(svm) ||
+                   !kvm_ghcb_cpl_is_valid(svm))
                        goto vmgexit_err;
                break;
        case SVM_EXIT_RDTSCP:
@@ -2514,19 +2518,19 @@ static int sev_es_validate_vmgexit(struct vcpu_svm *svm)
        case SVM_EXIT_WBINVD:
                break;
        case SVM_EXIT_MONITOR:
-               if (!ghcb_rax_is_valid(ghcb) ||
-                   !ghcb_rcx_is_valid(ghcb) ||
-                   !ghcb_rdx_is_valid(ghcb))
+               if (!kvm_ghcb_rax_is_valid(svm) ||
+                   !kvm_ghcb_rcx_is_valid(svm) ||
+                   !kvm_ghcb_rdx_is_valid(svm))
                        goto vmgexit_err;
                break;
        case SVM_EXIT_MWAIT:
-               if (!ghcb_rax_is_valid(ghcb) ||
-                   !ghcb_rcx_is_valid(ghcb))
+               if (!kvm_ghcb_rax_is_valid(svm) ||
+                   !kvm_ghcb_rcx_is_valid(svm))
                        goto vmgexit_err;
                break;
        case SVM_VMGEXIT_MMIO_READ:
        case SVM_VMGEXIT_MMIO_WRITE:
-               if (!ghcb_sw_scratch_is_valid(ghcb))
+               if (!kvm_ghcb_sw_scratch_is_valid(svm))
                        goto vmgexit_err;
                break;
        case SVM_VMGEXIT_NMI_COMPLETE:
@@ -2556,9 +2560,6 @@ vmgexit_err:
                dump_ghcb(svm);
        }
 
-       /* Clear the valid entries fields */
-       memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap));
-
        ghcb_set_sw_exit_info_1(ghcb, 2);
        ghcb_set_sw_exit_info_2(ghcb, reason);
 
@@ -2579,7 +2580,7 @@ void sev_es_unmap_ghcb(struct vcpu_svm *svm)
                 */
                if (svm->sev_es.ghcb_sa_sync) {
                        kvm_write_guest(svm->vcpu.kvm,
-                                       ghcb_get_sw_scratch(svm->sev_es.ghcb),
+                                       svm->sev_es.sw_scratch,
                                        svm->sev_es.ghcb_sa,
                                        svm->sev_es.ghcb_sa_len);
                        svm->sev_es.ghcb_sa_sync = false;
@@ -2630,7 +2631,7 @@ static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len)
        u64 scratch_gpa_beg, scratch_gpa_end;
        void *scratch_va;
 
-       scratch_gpa_beg = ghcb_get_sw_scratch(ghcb);
+       scratch_gpa_beg = svm->sev_es.sw_scratch;
        if (!scratch_gpa_beg) {
                pr_err("vmgexit: scratch gpa not provided\n");
                goto e_scratch;
@@ -2846,11 +2847,11 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu)
 
        exit_code = ghcb_get_sw_exit_code(ghcb);
 
+       sev_es_sync_from_ghcb(svm);
        ret = sev_es_validate_vmgexit(svm);
        if (ret)
                return ret;
 
-       sev_es_sync_from_ghcb(svm);
        ghcb_set_sw_exit_info_1(ghcb, 0);
        ghcb_set_sw_exit_info_2(ghcb, 0);