diff options
Diffstat (limited to 'arch/x86/kvm/svm.c')
-rw-r--r-- | arch/x86/kvm/svm.c | 248 |
1 files changed, 169 insertions, 79 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index ba9891ac5c56..4d8141e533c3 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -36,6 +36,7 @@ #include <linux/slab.h> #include <linux/amd-iommu.h> #include <linux/hashtable.h> +#include <linux/frame.h> #include <asm/apic.h> #include <asm/perf_event.h> @@ -189,10 +190,10 @@ struct vcpu_svm { struct nested_state nested; bool nmi_singlestep; + u64 nmi_singlestep_guest_rflags; unsigned int3_injected; unsigned long int3_rip; - u32 apf_reason; /* cached guest cpuid flags for faster access */ bool nrips_enabled : 1; @@ -275,6 +276,10 @@ static int avic; module_param(avic, int, S_IRUGO); #endif +/* enable/disable Virtual VMLOAD VMSAVE */ +static int vls = true; +module_param(vls, int, 0444); + /* AVIC VM ID bit masks and lock */ static DECLARE_BITMAP(avic_vm_id_bitmap, AVIC_VM_ID_NR); static DEFINE_SPINLOCK(avic_vm_id_lock); @@ -631,11 +636,13 @@ static void skip_emulated_instruction(struct kvm_vcpu *vcpu) svm_set_interrupt_shadow(vcpu, 0); } -static void svm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr, - bool has_error_code, u32 error_code, - bool reinject) +static void svm_queue_exception(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); + unsigned nr = vcpu->arch.exception.nr; + bool has_error_code = vcpu->arch.exception.has_error_code; + bool reinject = vcpu->arch.exception.reinject; + u32 error_code = vcpu->arch.exception.error_code; /* * If we are within a nested VM we'd better #VMEXIT and let the guest @@ -945,7 +952,7 @@ static void svm_enable_lbrv(struct vcpu_svm *svm) { u32 *msrpm = svm->msrpm; - svm->vmcb->control.lbr_ctl = 1; + svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK; set_msr_interception(msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1); set_msr_interception(msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1); set_msr_interception(msrpm, MSR_IA32_LASTINTFROMIP, 1, 1); @@ -956,13 +963,25 @@ static void svm_disable_lbrv(struct vcpu_svm *svm) { u32 *msrpm = svm->msrpm; - svm->vmcb->control.lbr_ctl = 0; + svm->vmcb->control.virt_ext &= ~LBR_CTL_ENABLE_MASK; set_msr_interception(msrpm, MSR_IA32_LASTBRANCHFROMIP, 0, 0); set_msr_interception(msrpm, MSR_IA32_LASTBRANCHTOIP, 0, 0); set_msr_interception(msrpm, MSR_IA32_LASTINTFROMIP, 0, 0); set_msr_interception(msrpm, MSR_IA32_LASTINTTOIP, 0, 0); } +static void disable_nmi_singlestep(struct vcpu_svm *svm) +{ + svm->nmi_singlestep = false; + if (!(svm->vcpu.guest_debug & KVM_GUESTDBG_SINGLESTEP)) { + /* Clear our flags if they were not set by the guest */ + if (!(svm->nmi_singlestep_guest_rflags & X86_EFLAGS_TF)) + svm->vmcb->save.rflags &= ~X86_EFLAGS_TF; + if (!(svm->nmi_singlestep_guest_rflags & X86_EFLAGS_RF)) + svm->vmcb->save.rflags &= ~X86_EFLAGS_RF; + } +} + /* Note: * This hash table is used to map VM_ID to a struct kvm_arch, * when handling AMD IOMMU GALOG notification to schedule in @@ -1079,6 +1098,16 @@ static __init int svm_hardware_setup(void) } } + if (vls) { + if (!npt_enabled || + !boot_cpu_has(X86_FEATURE_VIRTUAL_VMLOAD_VMSAVE) || + !IS_ENABLED(CONFIG_X86_64)) { + vls = false; + } else { + pr_info("Virtual VMLOAD VMSAVE supported\n"); + } + } + return 0; err: @@ -1266,6 +1295,16 @@ static void init_vmcb(struct vcpu_svm *svm) if (avic) avic_init_vmcb(svm); + /* + * If hardware supports Virtual VMLOAD VMSAVE then enable it + * in VMCB and clear intercepts to avoid #VMEXIT. + */ + if (vls) { + clr_intercept(svm, INTERCEPT_VMLOAD); + clr_intercept(svm, INTERCEPT_VMSAVE); + svm->vmcb->control.virt_ext |= VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK; + } + mark_all_dirty(svm->vmcb); enable_gif(svm); @@ -1712,11 +1751,24 @@ static void svm_vcpu_unblocking(struct kvm_vcpu *vcpu) static unsigned long svm_get_rflags(struct kvm_vcpu *vcpu) { - return to_svm(vcpu)->vmcb->save.rflags; + struct vcpu_svm *svm = to_svm(vcpu); + unsigned long rflags = svm->vmcb->save.rflags; + + if (svm->nmi_singlestep) { + /* Hide our flags if they were not set by the guest */ + if (!(svm->nmi_singlestep_guest_rflags & X86_EFLAGS_TF)) + rflags &= ~X86_EFLAGS_TF; + if (!(svm->nmi_singlestep_guest_rflags & X86_EFLAGS_RF)) + rflags &= ~X86_EFLAGS_RF; + } + return rflags; } static void svm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags) { + if (to_svm(vcpu)->nmi_singlestep) + rflags |= (X86_EFLAGS_TF | X86_EFLAGS_RF); + /* * Any change of EFLAGS.VM is accompanied by a reload of SS * (caused by either a task switch or an inter-privilege IRET), @@ -2069,34 +2121,11 @@ static void svm_set_dr7(struct kvm_vcpu *vcpu, unsigned long value) static int pf_interception(struct vcpu_svm *svm) { u64 fault_address = svm->vmcb->control.exit_info_2; - u64 error_code; - int r = 1; - - switch (svm->apf_reason) { - default: - error_code = svm->vmcb->control.exit_info_1; + u64 error_code = svm->vmcb->control.exit_info_1; - trace_kvm_page_fault(fault_address, error_code); - if (!npt_enabled && kvm_event_needs_reinjection(&svm->vcpu)) - kvm_mmu_unprotect_page_virt(&svm->vcpu, fault_address); - r = kvm_mmu_page_fault(&svm->vcpu, fault_address, error_code, + return kvm_handle_page_fault(&svm->vcpu, error_code, fault_address, svm->vmcb->control.insn_bytes, - svm->vmcb->control.insn_len); - break; - case KVM_PV_REASON_PAGE_NOT_PRESENT: - svm->apf_reason = 0; - local_irq_disable(); - kvm_async_pf_task_wait(fault_address); - local_irq_enable(); - break; - case KVM_PV_REASON_PAGE_READY: - svm->apf_reason = 0; - local_irq_disable(); - kvm_async_pf_task_wake(fault_address); - local_irq_enable(); - break; - } - return r; + svm->vmcb->control.insn_len, !npt_enabled); } static int db_interception(struct vcpu_svm *svm) @@ -2111,10 +2140,7 @@ static int db_interception(struct vcpu_svm *svm) } if (svm->nmi_singlestep) { - svm->nmi_singlestep = false; - if (!(svm->vcpu.guest_debug & KVM_GUESTDBG_SINGLESTEP)) - svm->vmcb->save.rflags &= - ~(X86_EFLAGS_TF | X86_EFLAGS_RF); + disable_nmi_singlestep(svm); } if (svm->vcpu.guest_debug & @@ -2243,7 +2269,7 @@ static int io_interception(struct vcpu_svm *svm) { struct kvm_vcpu *vcpu = &svm->vcpu; u32 io_info = svm->vmcb->control.exit_info_1; /* address size bug? */ - int size, in, string; + int size, in, string, ret; unsigned port; ++svm->vcpu.stat.io_exits; @@ -2255,10 +2281,16 @@ static int io_interception(struct vcpu_svm *svm) port = io_info >> 16; size = (io_info & SVM_IOIO_SIZE_MASK) >> SVM_IOIO_SIZE_SHIFT; svm->next_rip = svm->vmcb->control.exit_info_2; - skip_emulated_instruction(&svm->vcpu); + ret = kvm_skip_emulated_instruction(&svm->vcpu); - return in ? kvm_fast_pio_in(vcpu, size, port) - : kvm_fast_pio_out(vcpu, size, port); + /* + * TODO: we might be squashing a KVM_GUESTDBG_SINGLESTEP-triggered + * KVM_EXIT_DEBUG here. + */ + if (in) + return kvm_fast_pio_in(vcpu, size, port) && ret; + else + return kvm_fast_pio_out(vcpu, size, port) && ret; } static int nmi_interception(struct vcpu_svm *svm) @@ -2369,8 +2401,8 @@ static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu) static int nested_svm_check_permissions(struct vcpu_svm *svm) { - if (!(svm->vcpu.arch.efer & EFER_SVME) - || !is_paging(&svm->vcpu)) { + if (!(svm->vcpu.arch.efer & EFER_SVME) || + !is_paging(&svm->vcpu)) { kvm_queue_exception(&svm->vcpu, UD_VECTOR); return 1; } @@ -2380,7 +2412,7 @@ static int nested_svm_check_permissions(struct vcpu_svm *svm) return 1; } - return 0; + return 0; } static int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, @@ -2391,15 +2423,19 @@ static int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, if (!is_guest_mode(&svm->vcpu)) return 0; + vmexit = nested_svm_intercept(svm); + if (vmexit != NESTED_EXIT_DONE) + return 0; + 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; - - vmexit = nested_svm_intercept(svm); - if (vmexit == NESTED_EXIT_DONE) - svm->nested.exit_required = true; + if (svm->vcpu.arch.exception.nested_apf) + svm->vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token; + else + svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2; + svm->nested.exit_required = true; return vmexit; } @@ -2533,6 +2569,31 @@ static int nested_svm_exit_handled_msr(struct vcpu_svm *svm) return (value & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST; } +/* DB exceptions for our internal use must not cause vmexit */ +static int nested_svm_intercept_db(struct vcpu_svm *svm) +{ + unsigned long dr6; + + /* if we're not singlestepping, it's not ours */ + if (!svm->nmi_singlestep) + return NESTED_EXIT_DONE; + + /* if it's not a singlestep exception, it's not ours */ + if (kvm_get_dr(&svm->vcpu, 6, &dr6)) + return NESTED_EXIT_DONE; + if (!(dr6 & DR6_BS)) + return NESTED_EXIT_DONE; + + /* if the guest is singlestepping, it should get the vmexit */ + if (svm->nmi_singlestep_guest_rflags & X86_EFLAGS_TF) { + disable_nmi_singlestep(svm); + return NESTED_EXIT_DONE; + } + + /* it's ours, the nested hypervisor must not see this one */ + return NESTED_EXIT_HOST; +} + static int nested_svm_exit_special(struct vcpu_svm *svm) { u32 exit_code = svm->vmcb->control.exit_code; @@ -2549,7 +2610,7 @@ static int nested_svm_exit_special(struct vcpu_svm *svm) break; case SVM_EXIT_EXCP_BASE + PF_VECTOR: /* When we're shadowing, trap PFs, but not async PF */ - if (!npt_enabled && svm->apf_reason == 0) + if (!npt_enabled && svm->vcpu.arch.apf.host_apf_reason == 0) return NESTED_EXIT_HOST; break; default: @@ -2588,11 +2649,15 @@ static int nested_svm_intercept(struct vcpu_svm *svm) } case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: { u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE); - if (svm->nested.intercept_exceptions & excp_bits) - vmexit = NESTED_EXIT_DONE; + if (svm->nested.intercept_exceptions & excp_bits) { + if (exit_code == SVM_EXIT_EXCP_BASE + DB_VECTOR) + vmexit = nested_svm_intercept_db(svm); + else + vmexit = NESTED_EXIT_DONE; + } /* async page fault always cause vmexit */ else if ((exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR) && - svm->apf_reason != 0) + svm->vcpu.arch.exception.nested_apf != 0) vmexit = NESTED_EXIT_DONE; break; } @@ -2649,7 +2714,7 @@ static inline void copy_vmcb_control_area(struct vmcb *dst_vmcb, struct vmcb *fr dst->event_inj = from->event_inj; dst->event_inj_err = from->event_inj_err; dst->nested_cr3 = from->nested_cr3; - dst->lbr_ctl = from->lbr_ctl; + dst->virt_ext = from->virt_ext; } static int nested_svm_vmexit(struct vcpu_svm *svm) @@ -2955,7 +3020,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm) /* We don't want to see VMMCALLs from a nested guest */ clr_intercept(svm, INTERCEPT_VMMCALL); - svm->vmcb->control.lbr_ctl = nested_vmcb->control.lbr_ctl; + svm->vmcb->control.virt_ext = nested_vmcb->control.virt_ext; svm->vmcb->control.int_vector = nested_vmcb->control.int_vector; svm->vmcb->control.int_state = nested_vmcb->control.int_state; svm->vmcb->control.tsc_offset += nested_vmcb->control.tsc_offset; @@ -3002,6 +3067,7 @@ static int vmload_interception(struct vcpu_svm *svm) { struct vmcb *nested_vmcb; struct page *page; + int ret; if (nested_svm_check_permissions(svm)) return 1; @@ -3011,18 +3077,19 @@ static int vmload_interception(struct vcpu_svm *svm) return 1; svm->next_rip = kvm_rip_read(&svm->vcpu) + 3; - skip_emulated_instruction(&svm->vcpu); + ret = kvm_skip_emulated_instruction(&svm->vcpu); nested_svm_vmloadsave(nested_vmcb, svm->vmcb); nested_svm_unmap(page); - return 1; + return ret; } static int vmsave_interception(struct vcpu_svm *svm) { struct vmcb *nested_vmcb; struct page *page; + int ret; if (nested_svm_check_permissions(svm)) return 1; @@ -3032,12 +3099,12 @@ static int vmsave_interception(struct vcpu_svm *svm) return 1; svm->next_rip = kvm_rip_read(&svm->vcpu) + 3; - skip_emulated_instruction(&svm->vcpu); + ret = kvm_skip_emulated_instruction(&svm->vcpu); nested_svm_vmloadsave(svm->vmcb, nested_vmcb); nested_svm_unmap(page); - return 1; + return ret; } static int vmrun_interception(struct vcpu_svm *svm) @@ -3070,25 +3137,29 @@ failed: static int stgi_interception(struct vcpu_svm *svm) { + int ret; + if (nested_svm_check_permissions(svm)) return 1; svm->next_rip = kvm_rip_read(&svm->vcpu) + 3; - skip_emulated_instruction(&svm->vcpu); + ret = kvm_skip_emulated_instruction(&svm->vcpu); kvm_make_request(KVM_REQ_EVENT, &svm->vcpu); enable_gif(svm); - return 1; + return ret; } static int clgi_interception(struct vcpu_svm *svm) { + int ret; + if (nested_svm_check_permissions(svm)) return 1; svm->next_rip = kvm_rip_read(&svm->vcpu) + 3; - skip_emulated_instruction(&svm->vcpu); + ret = kvm_skip_emulated_instruction(&svm->vcpu); disable_gif(svm); @@ -3099,7 +3170,7 @@ static int clgi_interception(struct vcpu_svm *svm) mark_dirty(svm->vmcb, VMCB_INTR); } - return 1; + return ret; } static int invlpga_interception(struct vcpu_svm *svm) @@ -3113,8 +3184,7 @@ static int invlpga_interception(struct vcpu_svm *svm) kvm_mmu_invlpg(vcpu, kvm_register_read(&svm->vcpu, VCPU_REGS_RAX)); svm->next_rip = kvm_rip_read(&svm->vcpu) + 3; - skip_emulated_instruction(&svm->vcpu); - return 1; + return kvm_skip_emulated_instruction(&svm->vcpu); } static int skinit_interception(struct vcpu_svm *svm) @@ -3137,7 +3207,7 @@ static int xsetbv_interception(struct vcpu_svm *svm) if (kvm_set_xcr(&svm->vcpu, index, new_bv) == 0) { svm->next_rip = kvm_rip_read(&svm->vcpu) + 3; - skip_emulated_instruction(&svm->vcpu); + return kvm_skip_emulated_instruction(&svm->vcpu); } return 1; @@ -3233,8 +3303,7 @@ static int invlpg_interception(struct vcpu_svm *svm) return emulate_instruction(&svm->vcpu, 0) == EMULATE_DONE; kvm_mmu_invlpg(&svm->vcpu, svm->vmcb->control.exit_info_1); - skip_emulated_instruction(&svm->vcpu); - return 1; + return kvm_skip_emulated_instruction(&svm->vcpu); } static int emulate_on_interception(struct vcpu_svm *svm) @@ -3384,9 +3453,7 @@ static int dr_interception(struct vcpu_svm *svm) kvm_register_write(&svm->vcpu, reg, val); } - skip_emulated_instruction(&svm->vcpu); - - return 1; + return kvm_skip_emulated_instruction(&svm->vcpu); } static int cr8_write_interception(struct vcpu_svm *svm) @@ -3509,6 +3576,7 @@ static int rdmsr_interception(struct vcpu_svm *svm) if (svm_get_msr(&svm->vcpu, &msr_info)) { trace_kvm_msr_read_ex(ecx); kvm_inject_gp(&svm->vcpu, 0); + return 1; } else { trace_kvm_msr_read(ecx, msr_info.data); @@ -3517,9 +3585,8 @@ static int rdmsr_interception(struct vcpu_svm *svm) kvm_register_write(&svm->vcpu, VCPU_REGS_RDX, msr_info.data >> 32); svm->next_rip = kvm_rip_read(&svm->vcpu) + 2; - skip_emulated_instruction(&svm->vcpu); + return kvm_skip_emulated_instruction(&svm->vcpu); } - return 1; } static int svm_set_vm_cr(struct kvm_vcpu *vcpu, u64 data) @@ -3645,11 +3712,11 @@ static int wrmsr_interception(struct vcpu_svm *svm) if (kvm_set_msr(&svm->vcpu, &msr)) { trace_kvm_msr_write_ex(ecx, data); kvm_inject_gp(&svm->vcpu, 0); + return 1; } else { trace_kvm_msr_write(ecx, data); - skip_emulated_instruction(&svm->vcpu); + return kvm_skip_emulated_instruction(&svm->vcpu); } - return 1; } static int msr_interception(struct vcpu_svm *svm) @@ -3678,8 +3745,7 @@ static int pause_interception(struct vcpu_svm *svm) static int nop_interception(struct vcpu_svm *svm) { - skip_emulated_instruction(&(svm->vcpu)); - return 1; + return kvm_skip_emulated_instruction(&(svm->vcpu)); } static int monitor_interception(struct vcpu_svm *svm) @@ -4064,7 +4130,7 @@ static void dump_vmcb(struct kvm_vcpu *vcpu) pr_err("%-20s%016llx\n", "avic_vapic_bar:", control->avic_vapic_bar); pr_err("%-20s%08x\n", "event_inj:", control->event_inj); pr_err("%-20s%08x\n", "event_inj_err:", control->event_inj_err); - pr_err("%-20s%lld\n", "lbr_ctl:", control->lbr_ctl); + pr_err("%-20s%lld\n", "virt_ext:", control->virt_ext); pr_err("%-20s%016llx\n", "next_rip:", control->next_rip); pr_err("%-20s%016llx\n", "avic_backing_page:", control->avic_backing_page); pr_err("%-20s%016llx\n", "avic_logical_id:", control->avic_logical_id); @@ -4626,10 +4692,17 @@ static void enable_nmi_window(struct kvm_vcpu *vcpu) == HF_NMI_MASK) return; /* IRET will cause a vm exit */ + if ((svm->vcpu.arch.hflags & HF_GIF_MASK) == 0) + return; /* STGI will cause a vm exit */ + + if (svm->nested.exit_required) + return; /* we're not going to run the guest yet */ + /* * Something prevents NMI from been injected. Single step over possible * problem (IRET or exception injection or interrupt shadow) */ + svm->nmi_singlestep_guest_rflags = svm_get_rflags(vcpu); svm->nmi_singlestep = true; svm->vmcb->save.rflags |= (X86_EFLAGS_TF | X86_EFLAGS_RF); } @@ -4770,6 +4843,22 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu) if (unlikely(svm->nested.exit_required)) return; + /* + * Disable singlestep if we're injecting an interrupt/exception. + * We don't want our modified rflags to be pushed on the stack where + * we might not be able to easily reset them if we disabled NMI + * singlestep later. + */ + if (svm->nmi_singlestep && svm->vmcb->control.event_inj) { + /* + * Event injection happens before external interrupts cause a + * vmexit and interrupts are disabled here, so smp_send_reschedule + * is enough to force an immediate vmexit. + */ + disable_nmi_singlestep(svm); + smp_send_reschedule(vcpu->cpu); + } + pre_svm_run(svm); sync_lapic_to_cr8(vcpu); @@ -4889,7 +4978,7 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu) /* if exit due to PF check for async PF */ if (svm->vmcb->control.exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR) - svm->apf_reason = kvm_read_and_reset_pf_reason(); + svm->vcpu.arch.apf.host_apf_reason = kvm_read_and_reset_pf_reason(); if (npt_enabled) { vcpu->arch.regs_avail &= ~(1 << VCPU_EXREG_PDPTR); @@ -4906,6 +4995,7 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu) mark_all_clean(svm->vmcb); } +STACK_FRAME_NON_STANDARD(svm_vcpu_run); static void svm_set_cr3(struct kvm_vcpu *vcpu, unsigned long root) { |