diff options
| -rw-r--r-- | arch/x86/kvm/svm.c | 293 |
1 files changed, 293 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index fad187cbfab..4cb2920b152 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -72,6 +72,13 @@ module_param(npt, int, S_IRUGO); static void kvm_reput_irq(struct vcpu_svm *svm); static void svm_flush_tlb(struct kvm_vcpu *vcpu); +static int nested_svm_exit_handled(struct vcpu_svm *svm, bool kvm_override); +static int nested_svm_vmexit(struct vcpu_svm *svm); +static int nested_svm_vmsave(struct vcpu_svm *svm, void *nested_vmcb, + void *arg2, void *opaque); +static int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, + bool has_error_code, u32 error_code); + static inline struct vcpu_svm *to_svm(struct kvm_vcpu *vcpu) { return container_of(vcpu, struct vcpu_svm, vcpu); @@ -221,6 +228,11 @@ static void svm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr, { struct vcpu_svm *svm = to_svm(vcpu); + /* If we are within a nested VM we'd better #VMEXIT and let the + guest handle the exception */ + if (nested_svm_check_exception(svm, nr, has_error_code, error_code)) + return; + svm->vmcb->control.event_inj = nr | SVM_EVTINJ_VALID | (has_error_code ? SVM_EVTINJ_VALID_ERR : 0) @@ -1198,6 +1210,46 @@ static int nested_svm_check_permissions(struct vcpu_svm *svm) return 0; } +static int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, + bool has_error_code, u32 error_code) +{ + if (is_nested(svm)) { + svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr; + svm->vmcb->control.exit_code_hi = 0; + svm->vmcb->control.exit_info_1 = error_code; + svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2; + if (nested_svm_exit_handled(svm, false)) { + nsvm_printk("VMexit -> EXCP 0x%x\n", nr); + + nested_svm_vmexit(svm); + return 1; + } + } + + return 0; +} + +static inline int nested_svm_intr(struct vcpu_svm *svm) +{ + if (is_nested(svm)) { + if (!(svm->vcpu.arch.hflags & HF_VINTR_MASK)) + return 0; + + if (!(svm->vcpu.arch.hflags & HF_HIF_MASK)) + return 0; + + svm->vmcb->control.exit_code = SVM_EXIT_INTR; + + if (nested_svm_exit_handled(svm, false)) { + nsvm_printk("VMexit -> INTR\n"); + nested_svm_vmexit(svm); + return 1; + } + } + + return 0; +} + static struct page *nested_svm_get_page(struct vcpu_svm *svm, u64 gpa) { struct page *page; @@ -1258,6 +1310,228 @@ static int nested_svm_do(struct vcpu_svm *svm, return retval; } +static int nested_svm_exit_handled_real(struct vcpu_svm *svm, + void *arg1, + void *arg2, + void *opaque) +{ + struct vmcb *nested_vmcb = (struct vmcb *)arg1; + bool kvm_overrides = *(bool *)opaque; + u32 exit_code = svm->vmcb->control.exit_code; + + if (kvm_overrides) { + switch (exit_code) { + case SVM_EXIT_INTR: + case SVM_EXIT_NMI: + return 0; + /* For now we are always handling NPFs when using them */ + case SVM_EXIT_NPF: + if (npt_enabled) + return 0; + break; + /* When we're shadowing, trap PFs */ + case SVM_EXIT_EXCP_BASE + PF_VECTOR: + if (!npt_enabled) + return 0; + break; + default: + break; + } + } + + switch (exit_code) { + case SVM_EXIT_READ_CR0 ... SVM_EXIT_READ_CR8: { + u32 cr_bits = 1 << (exit_code - SVM_EXIT_READ_CR0); + if (nested_vmcb->control.intercept_cr_read & cr_bits) + return 1; + break; + } + case SVM_EXIT_WRITE_CR0 ... SVM_EXIT_WRITE_CR8: { + u32 cr_bits = 1 << (exit_code - SVM_EXIT_WRITE_CR0); + if (nested_vmcb->control.intercept_cr_write & cr_bits) + return 1; + break; + } + case SVM_EXIT_READ_DR0 ... SVM_EXIT_READ_DR7: { + u32 dr_bits = 1 << (exit_code - SVM_EXIT_READ_DR0); + if (nested_vmcb->control.intercept_dr_read & dr_bits) + return 1; + break; + } + case SVM_EXIT_WRITE_DR0 ... SVM_EXIT_WRITE_DR7: { + u32 dr_bits = 1 << (exit_code - SVM_EXIT_WRITE_DR0); + if (nested_vmcb->control.intercept_dr_write & dr_bits) + return 1; + break; + } + case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: { + u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE); + if (nested_vmcb->control.intercept_exceptions & excp_bits) + return 1; + break; + } + default: { + u64 exit_bits = 1ULL << (exit_code - SVM_EXIT_INTR); + nsvm_printk("exit code: 0x%x\n", exit_code); + if (nested_vmcb->control.intercept & exit_bits) + return 1; + } + } + + return 0; +} + +static int nested_svm_exit_handled_msr(struct vcpu_svm *svm, + void *arg1, void *arg2, + void *opaque) +{ + struct vmcb *nested_vmcb = (struct vmcb *)arg1; + u8 *msrpm = (u8 *)arg2; + u32 t0, t1; + u32 msr = svm->vcpu.arch.regs[VCPU_REGS_RCX]; + u32 param = svm->vmcb->control.exit_info_1 & 1; + + if (!(nested_vmcb->control.intercept & (1ULL << INTERCEPT_MSR_PROT))) + return 0; + + switch(msr) { + case 0 ... 0x1fff: + t0 = (msr * 2) % 8; + t1 = msr / 8; + break; + case 0xc0000000 ... 0xc0001fff: + t0 = (8192 + msr - 0xc0000000) * 2; + t1 = (t0 / 8); + t0 %= 8; + break; + case 0xc0010000 ... 0xc0011fff: + t0 = (16384 + msr - 0xc0010000) * 2; + t1 = (t0 / 8); + t0 %= 8; + break; + default: + return 1; + break; + } + if (msrpm[t1] & ((1 << param) << t0)) + return 1; + + return 0; +} + +static int nested_svm_exit_handled(struct vcpu_svm *svm, bool kvm_override) +{ + bool k = kvm_override; + + switch (svm->vmcb->control.exit_code) { + case SVM_EXIT_MSR: + return nested_svm_do(svm, svm->nested_vmcb, + svm->nested_vmcb_msrpm, NULL, + nested_svm_exit_handled_msr); + default: break; + } + + return nested_svm_do(svm, svm->nested_vmcb, 0, &k, + nested_svm_exit_handled_real); +} + +static int nested_svm_vmexit_real(struct vcpu_svm *svm, void *arg1, + void *arg2, void *opaque) +{ + struct vmcb *nested_vmcb = (struct vmcb *)arg1; + struct vmcb *hsave = svm->hsave; + u64 nested_save[] = { nested_vmcb->save.cr0, + nested_vmcb->save.cr3, + nested_vmcb->save.cr4, + nested_vmcb->save.efer, + nested_vmcb->control.intercept_cr_read, + nested_vmcb->control.intercept_cr_write, + nested_vmcb->control.intercept_dr_read, + nested_vmcb->control.intercept_dr_write, + nested_vmcb->control.intercept_exceptions, + nested_vmcb->control.intercept, + nested_vmcb->control.msrpm_base_pa, + nested_vmcb->control.iopm_base_pa, + nested_vmcb->control.tsc_offset }; + + /* Give the current vmcb to the guest */ + memcpy(nested_vmcb, svm->vmcb, sizeof(struct vmcb)); + nested_vmcb->save.cr0 = nested_save[0]; + if (!npt_enabled) + nested_vmcb->save.cr3 = nested_save[1]; + nested_vmcb->save.cr4 = nested_save[2]; + nested_vmcb->save.efer = nested_save[3]; + nested_vmcb->control.intercept_cr_read = nested_save[4]; + nested_vmcb->control.intercept_cr_write = nested_save[5]; + nested_vmcb->control.intercept_dr_read = nested_save[6]; + nested_vmcb->control.intercept_dr_write = nested_save[7]; + nested_vmcb->control.intercept_exceptions = nested_save[8]; + nested_vmcb->control.intercept = nested_save[9]; + nested_vmcb->control.msrpm_base_pa = nested_save[10]; + nested_vmcb->control.iopm_base_pa = nested_save[11]; + nested_vmcb->control.tsc_offset = nested_save[12]; + + /* We always set V_INTR_MASKING and remember the old value in hflags */ + if (!(svm->vcpu.arch.hflags & HF_VINTR_MASK)) + nested_vmcb->control.int_ctl &= ~V_INTR_MASKING_MASK; + + if ((nested_vmcb->control.int_ctl & V_IRQ_MASK) && + (nested_vmcb->control.int_vector)) { + nsvm_printk("WARNING: IRQ 0x%x still enabled on #VMEXIT\n", + nested_vmcb->control.int_vector); + } + + /* Restore the original control entries */ + svm->vmcb->control = hsave->control; + + /* Kill any pending exceptions */ + if (svm->vcpu.arch.exception.pending == true) + nsvm_printk("WARNING: Pending Exception\n"); + svm->vcpu.arch.exception.pending = false; + + /* Restore selected save entries */ + svm->vmcb->save.es = hsave->save.es; + svm->vmcb->save.cs = hsave->save.cs; + svm->vmcb->save.ss = hsave->save.ss; + svm->vmcb->save.ds = hsave->save.ds; + svm->vmcb->save.gdtr = hsave->save.gdtr; + svm->vmcb->save.idtr = hsave->save.idtr; + svm->vmcb->save.rflags = hsave->save.rflags; + svm_set_efer(&svm->vcpu, hsave->save.efer); + svm_set_cr0(&svm->vcpu, hsave->save.cr0 | X86_CR0_PE); + svm_set_cr4(&svm->vcpu, hsave->save.cr4); + if (npt_enabled) { + svm->vmcb->save.cr3 = hsave->save.cr3; + svm->vcpu.arch.cr3 = hsave->save.cr3; + } else { + kvm_set_cr3(&svm->vcpu, hsave->save.cr3); + } + kvm_register_write(&svm->vcpu, VCPU_REGS_RAX, hsave->save.rax); + kvm_register_write(&svm->vcpu, VCPU_REGS_RSP, hsave->save.rsp); + kvm_register_write(&svm->vcpu, VCPU_REGS_RIP, hsave->save.rip); + svm->vmcb->save.dr7 = 0; + svm->vmcb->save.cpl = 0; + svm->vmcb->control.exit_int_info = 0; + + svm->vcpu.arch.hflags &= ~HF_GIF_MASK; + /* Exit nested SVM mode */ + svm->nested_vmcb = 0; + + return 0; +} + +static int nested_svm_vmexit(struct vcpu_svm *svm) +{ + nsvm_printk("VMexit\n"); + if (nested_svm_do(svm, svm->nested_vmcb, 0, + NULL, nested_svm_vmexit_real)) + return 1; + + kvm_mmu_reset_context(&svm->vcpu); + kvm_mmu_load(&svm->vcpu); + + return 0; +} static int nested_svm_vmrun_msrpm(struct vcpu_svm *svm, void *arg1, void *arg2, void *opaque) @@ -1805,6 +2079,17 @@ static int handle_exit(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) KVMTRACE_3D(VMEXIT, vcpu, exit_code, (u32)svm->vmcb->save.rip, (u32)((u64)svm->vmcb->save.rip >> 32), entryexit); + if (is_nested(svm)) { + nsvm_printk("nested handle_exit: 0x%x | 0x%lx | 0x%lx | 0x%lx\n", + exit_code, svm->vmcb->control.exit_info_1, + svm->vmcb->control.exit_info_2, svm->vmcb->save.rip); + if (nested_svm_exit_handled(svm, true)) { + nested_svm_vmexit(svm); + nsvm_printk("-> #VMEXIT\n"); + return 1; + } + } + if (npt_enabled) { int mmu_reload = 0; if ((vcpu->arch.cr0 ^ svm->vmcb->save.cr0) & X86_CR0_PG) { @@ -1892,6 +2177,8 @@ static void svm_set_irq(struct kvm_vcpu *vcpu, int irq) { struct vcpu_svm *svm = to_svm(vcpu); + nested_svm_intr(svm); + svm_inject_irq(svm, irq); } @@ -1937,6 +2224,9 @@ static void svm_intr_assist(struct kvm_vcpu *vcpu) if (!kvm_cpu_has_interrupt(vcpu)) goto out; + if (nested_svm_intr(svm)) + goto out; + if (!(svm->vcpu.arch.hflags & HF_GIF_MASK)) goto out; @@ -1989,6 +2279,9 @@ static void do_interrupt_requests(struct kvm_vcpu *vcpu, struct vcpu_svm *svm = to_svm(vcpu); struct vmcb_control_area *control = &svm->vmcb->control; + if (nested_svm_intr(svm)) + return; + svm->vcpu.arch.interrupt_window_open = (!(control->int_state & SVM_INTERRUPT_SHADOW_MASK) && (svm->vmcb->save.rflags & X86_EFLAGS_IF) && |