From 6d03a247468059b0e59c821ef39e6762d4d6fc30 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 19 Jun 2024 23:00:51 +0200 Subject: Merging upstream version 6.9.2. Signed-off-by: Daniel Baumann --- arch/x86/kvm/vmx/vmx.c | 188 ++++++++++++++++++++++++++++--------------------- 1 file changed, 107 insertions(+), 81 deletions(-) (limited to 'arch/x86/kvm/vmx/vmx.c') diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 784f2ecca..22411f4af 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -38,6 +38,7 @@ #include #include #include +#include #include #include #include @@ -49,6 +50,8 @@ #include #include +#include + #include "capabilities.h" #include "cpuid.h" #include "hyperv.h" @@ -159,7 +162,7 @@ module_param(allow_smaller_maxphyaddr, bool, S_IRUGO); /* * List of MSRs that can be directly passed to the guest. - * In addition to these x2apic and PT MSRs are handled specially. + * In addition to these x2apic, PT and LBR MSRs are handled specially. */ static u32 vmx_possible_passthrough_msrs[MAX_POSSIBLE_PASSTHROUGH_MSRS] = { MSR_IA32_SPEC_CTRL, @@ -215,6 +218,8 @@ module_param(ple_window_max, uint, 0444); int __read_mostly pt_mode = PT_MODE_SYSTEM; module_param(pt_mode, int, S_IRUGO); +struct x86_pmu_lbr __ro_after_init vmx_lbr_caps; + static DEFINE_STATIC_KEY_FALSE(vmx_l1d_should_flush); static DEFINE_STATIC_KEY_FALSE(vmx_l1d_flush_cond); static DEFINE_MUTEX(vmx_l1d_flush_mutex); @@ -667,25 +672,14 @@ static inline bool cpu_need_virtualize_apic_accesses(struct kvm_vcpu *vcpu) return flexpriority_enabled && lapic_in_kernel(vcpu); } -static int possible_passthrough_msr_slot(u32 msr) -{ - u32 i; - - for (i = 0; i < ARRAY_SIZE(vmx_possible_passthrough_msrs); i++) - if (vmx_possible_passthrough_msrs[i] == msr) - return i; - - return -ENOENT; -} - -static bool is_valid_passthrough_msr(u32 msr) +static int vmx_get_passthrough_msr_slot(u32 msr) { - bool r; + int i; switch (msr) { case 0x800 ... 0x8ff: /* x2APIC MSRs. These are handled in vmx_update_msr_bitmap_x2apic() */ - return true; + return -ENOENT; case MSR_IA32_RTIT_STATUS: case MSR_IA32_RTIT_OUTPUT_BASE: case MSR_IA32_RTIT_OUTPUT_MASK: @@ -700,14 +694,16 @@ static bool is_valid_passthrough_msr(u32 msr) case MSR_LBR_CORE_FROM ... MSR_LBR_CORE_FROM + 8: case MSR_LBR_CORE_TO ... MSR_LBR_CORE_TO + 8: /* LBR MSRs. These are handled in vmx_update_intercept_for_lbr_msrs() */ - return true; + return -ENOENT; } - r = possible_passthrough_msr_slot(msr) != -ENOENT; - - WARN(!r, "Invalid MSR %x, please adapt vmx_possible_passthrough_msrs[]", msr); + for (i = 0; i < ARRAY_SIZE(vmx_possible_passthrough_msrs); i++) { + if (vmx_possible_passthrough_msrs[i] == msr) + return i; + } - return r; + WARN(1, "Invalid MSR %x, please adapt vmx_possible_passthrough_msrs[]", msr); + return -ENOENT; } struct vmx_uret_msr *vmx_find_uret_msr(struct vcpu_vmx *vmx, u32 msr) @@ -1290,8 +1286,6 @@ void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) u16 fs_sel, gs_sel; int i; - vmx->req_immediate_exit = false; - /* * Note that guest MSRs to be saved/restored can also be changed * when guest state is loaded. This happens when guest transitions @@ -3963,6 +3957,7 @@ void vmx_disable_intercept_for_msr(struct kvm_vcpu *vcpu, u32 msr, int type) { struct vcpu_vmx *vmx = to_vmx(vcpu); unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap; + int idx; if (!cpu_has_vmx_msr_bitmap()) return; @@ -3972,16 +3967,13 @@ void vmx_disable_intercept_for_msr(struct kvm_vcpu *vcpu, u32 msr, int type) /* * Mark the desired intercept state in shadow bitmap, this is needed * for resync when the MSR filters change. - */ - if (is_valid_passthrough_msr(msr)) { - int idx = possible_passthrough_msr_slot(msr); - - if (idx != -ENOENT) { - if (type & MSR_TYPE_R) - clear_bit(idx, vmx->shadow_msr_intercept.read); - if (type & MSR_TYPE_W) - clear_bit(idx, vmx->shadow_msr_intercept.write); - } + */ + idx = vmx_get_passthrough_msr_slot(msr); + if (idx >= 0) { + if (type & MSR_TYPE_R) + clear_bit(idx, vmx->shadow_msr_intercept.read); + if (type & MSR_TYPE_W) + clear_bit(idx, vmx->shadow_msr_intercept.write); } if ((type & MSR_TYPE_R) && @@ -4007,6 +3999,7 @@ void vmx_enable_intercept_for_msr(struct kvm_vcpu *vcpu, u32 msr, int type) { struct vcpu_vmx *vmx = to_vmx(vcpu); unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap; + int idx; if (!cpu_has_vmx_msr_bitmap()) return; @@ -4016,16 +4009,13 @@ void vmx_enable_intercept_for_msr(struct kvm_vcpu *vcpu, u32 msr, int type) /* * Mark the desired intercept state in shadow bitmap, this is needed * for resync when the MSR filter changes. - */ - if (is_valid_passthrough_msr(msr)) { - int idx = possible_passthrough_msr_slot(msr); - - if (idx != -ENOENT) { - if (type & MSR_TYPE_R) - set_bit(idx, vmx->shadow_msr_intercept.read); - if (type & MSR_TYPE_W) - set_bit(idx, vmx->shadow_msr_intercept.write); - } + */ + idx = vmx_get_passthrough_msr_slot(msr); + if (idx >= 0) { + if (type & MSR_TYPE_R) + set_bit(idx, vmx->shadow_msr_intercept.read); + if (type & MSR_TYPE_W) + set_bit(idx, vmx->shadow_msr_intercept.write); } if (type & MSR_TYPE_R) @@ -4136,6 +4126,9 @@ static void vmx_msr_filter_changed(struct kvm_vcpu *vcpu) struct vcpu_vmx *vmx = to_vmx(vcpu); u32 i; + if (!cpu_has_vmx_msr_bitmap()) + return; + /* * Redo intercept permissions for MSRs that KVM is passing through to * the guest. Disabling interception will check the new MSR filter and @@ -5575,10 +5568,7 @@ static int handle_dr(struct kvm_vcpu *vcpu) reg = DEBUG_REG_ACCESS_REG(exit_qualification); if (exit_qualification & TYPE_MOV_FROM_DR) { - unsigned long val; - - kvm_get_dr(vcpu, dr, &val); - kvm_register_write(vcpu, reg, val); + kvm_register_write(vcpu, reg, kvm_get_dr(vcpu, dr)); err = 0; } else { err = kvm_set_dr(vcpu, dr, kvm_register_read(vcpu, reg)); @@ -6000,22 +5990,46 @@ static int handle_pml_full(struct kvm_vcpu *vcpu) return 1; } -static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu) +static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu, + bool force_immediate_exit) { struct vcpu_vmx *vmx = to_vmx(vcpu); - if (!vmx->req_immediate_exit && - !unlikely(vmx->loaded_vmcs->hv_timer_soft_disabled)) { - kvm_lapic_expired_hv_timer(vcpu); + /* + * In the *extremely* unlikely scenario that this is a spurious VM-Exit + * due to the timer expiring while it was "soft" disabled, just eat the + * exit and re-enter the guest. + */ + if (unlikely(vmx->loaded_vmcs->hv_timer_soft_disabled)) return EXIT_FASTPATH_REENTER_GUEST; - } - return EXIT_FASTPATH_NONE; + /* + * If the timer expired because KVM used it to force an immediate exit, + * then mission accomplished. + */ + if (force_immediate_exit) + return EXIT_FASTPATH_EXIT_HANDLED; + + /* + * If L2 is active, go down the slow path as emulating the guest timer + * expiration likely requires synthesizing a nested VM-Exit. + */ + if (is_guest_mode(vcpu)) + return EXIT_FASTPATH_NONE; + + kvm_lapic_expired_hv_timer(vcpu); + return EXIT_FASTPATH_REENTER_GUEST; } static int handle_preemption_timer(struct kvm_vcpu *vcpu) { - handle_fastpath_preemption_timer(vcpu); + /* + * This non-fastpath handler is reached if and only if the preemption + * timer was being used to emulate a guest timer while L2 is active. + * All other scenarios are supposed to be handled in the fastpath. + */ + WARN_ON_ONCE(!is_guest_mode(vcpu)); + kvm_lapic_expired_hv_timer(vcpu); return 1; } @@ -6518,7 +6532,7 @@ static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_DELIVERY_EV; vcpu->run->internal.data[0] = vectoring_info; vcpu->run->internal.data[1] = exit_reason.full; - vcpu->run->internal.data[2] = vcpu->arch.exit_qualification; + vcpu->run->internal.data[2] = vmx_get_exit_qual(vcpu); if (exit_reason.basic == EXIT_REASON_EPT_MISCONFIG) { vcpu->run->internal.data[ndata++] = vmcs_read64(GUEST_PHYSICAL_ADDRESS); @@ -6552,7 +6566,7 @@ static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) if (exit_reason.basic >= kvm_vmx_max_exit_handlers) goto unexpected_vmexit; -#ifdef CONFIG_RETPOLINE +#ifdef CONFIG_MITIGATION_RETPOLINE if (exit_reason.basic == EXIT_REASON_MSR_WRITE) return kvm_emulate_wrmsr(vcpu); else if (exit_reason.basic == EXIT_REASON_PREEMPTION_TIMER) @@ -6969,14 +6983,16 @@ static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu) { u32 intr_info = vmx_get_intr_info(vcpu); unsigned int vector = intr_info & INTR_INFO_VECTOR_MASK; - gate_desc *desc = (gate_desc *)host_idt_base + vector; if (KVM_BUG(!is_external_intr(intr_info), vcpu->kvm, "unexpected VM-Exit interrupt info: 0x%x", intr_info)) return; kvm_before_interrupt(vcpu, KVM_HANDLING_IRQ); - vmx_do_interrupt_irqoff(gate_offset(desc)); + if (cpu_feature_enabled(X86_FEATURE_FRED)) + fred_entry_from_kvm(EVENT_TYPE_EXTINT, vector); + else + vmx_do_interrupt_irqoff(gate_offset((gate_desc *)host_idt_base + vector)); kvm_after_interrupt(vcpu); vcpu->arch.at_instruction_boundary = true; @@ -7155,13 +7171,13 @@ static void atomic_switch_perf_msrs(struct vcpu_vmx *vmx) msrs[i].host, false); } -static void vmx_update_hv_timer(struct kvm_vcpu *vcpu) +static void vmx_update_hv_timer(struct kvm_vcpu *vcpu, bool force_immediate_exit) { struct vcpu_vmx *vmx = to_vmx(vcpu); u64 tscl; u32 delta_tsc; - if (vmx->req_immediate_exit) { + if (force_immediate_exit) { vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, 0); vmx->loaded_vmcs->hv_timer_soft_disabled = false; } else if (vmx->hv_deadline_tsc != -1) { @@ -7214,13 +7230,22 @@ void noinstr vmx_spec_ctrl_restore_host(struct vcpu_vmx *vmx, barrier_nospec(); } -static fastpath_t vmx_exit_handlers_fastpath(struct kvm_vcpu *vcpu) +static fastpath_t vmx_exit_handlers_fastpath(struct kvm_vcpu *vcpu, + bool force_immediate_exit) { + /* + * If L2 is active, some VMX preemption timer exits can be handled in + * the fastpath even, all other exits must use the slow path. + */ + if (is_guest_mode(vcpu) && + to_vmx(vcpu)->exit_reason.basic != EXIT_REASON_PREEMPTION_TIMER) + return EXIT_FASTPATH_NONE; + switch (to_vmx(vcpu)->exit_reason.basic) { case EXIT_REASON_MSR_WRITE: return handle_fastpath_set_msr_irqoff(vcpu); case EXIT_REASON_PREEMPTION_TIMER: - return handle_fastpath_preemption_timer(vcpu); + return handle_fastpath_preemption_timer(vcpu, force_immediate_exit); default: return EXIT_FASTPATH_NONE; } @@ -7272,7 +7297,10 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu, if ((u16)vmx->exit_reason.basic == EXIT_REASON_EXCEPTION_NMI && is_nmi(vmx_get_intr_info(vcpu))) { kvm_before_interrupt(vcpu, KVM_HANDLING_NMI); - vmx_do_nmi_irqoff(); + if (cpu_feature_enabled(X86_FEATURE_FRED)) + fred_entry_from_kvm(EVENT_TYPE_NMI, NMI_VECTOR); + else + vmx_do_nmi_irqoff(); kvm_after_interrupt(vcpu); } @@ -7280,7 +7308,7 @@ out: guest_state_exit_irqoff(); } -static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) +static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu, bool force_immediate_exit) { struct vcpu_vmx *vmx = to_vmx(vcpu); unsigned long cr3, cr4; @@ -7307,7 +7335,7 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) return EXIT_FASTPATH_NONE; } - trace_kvm_entry(vcpu); + trace_kvm_entry(vcpu, force_immediate_exit); if (vmx->ple_window_dirty) { vmx->ple_window_dirty = false; @@ -7366,7 +7394,9 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) vmx_passthrough_lbr_msrs(vcpu); if (enable_preemption_timer) - vmx_update_hv_timer(vcpu); + vmx_update_hv_timer(vcpu, force_immediate_exit); + else if (force_immediate_exit) + smp_send_reschedule(vcpu->cpu); kvm_wait_lapic_expire(vcpu); @@ -7430,10 +7460,7 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) vmx_recover_nmi_blocking(vmx); vmx_complete_interrupts(vmx); - if (is_guest_mode(vcpu)) - return EXIT_FASTPATH_NONE; - - return vmx_exit_handlers_fastpath(vcpu); + return vmx_exit_handlers_fastpath(vcpu, force_immediate_exit); } static void vmx_vcpu_free(struct kvm_vcpu *vcpu) @@ -7837,10 +7864,9 @@ static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) vmx_update_exception_bitmap(vcpu); } -static u64 vmx_get_perf_capabilities(void) +static __init u64 vmx_get_perf_capabilities(void) { u64 perf_cap = PMU_CAP_FW_WRITES; - struct x86_pmu_lbr lbr; u64 host_perf_cap = 0; if (!enable_pmu) @@ -7850,8 +7876,16 @@ static u64 vmx_get_perf_capabilities(void) rdmsrl(MSR_IA32_PERF_CAPABILITIES, host_perf_cap); if (!cpu_feature_enabled(X86_FEATURE_ARCH_LBR)) { - x86_perf_get_lbr(&lbr); - if (lbr.nr) + x86_perf_get_lbr(&vmx_lbr_caps); + + /* + * KVM requires LBR callstack support, as the overhead due to + * context switching LBRs without said support is too high. + * See intel_pmu_create_guest_lbr_event() for more info. + */ + if (!vmx_lbr_caps.has_callstack) + memset(&vmx_lbr_caps, 0, sizeof(vmx_lbr_caps)); + else if (vmx_lbr_caps.nr) perf_cap |= host_perf_cap & PMU_CAP_LBR_FMT; } @@ -7933,11 +7967,6 @@ static __init void vmx_set_cpu_caps(void) kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG); } -static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu) -{ - to_vmx(vcpu)->req_immediate_exit = true; -} - static int vmx_check_intercept_io(struct kvm_vcpu *vcpu, struct x86_instruction_info *info) { @@ -8390,8 +8419,6 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { .check_intercept = vmx_check_intercept, .handle_exit_irqoff = vmx_handle_exit_irqoff, - .request_immediate_exit = vmx_request_immediate_exit, - .sched_in = vmx_sched_in, .cpu_dirty_log_size = PML_ENTITY_NUM, @@ -8651,7 +8678,6 @@ static __init int hardware_setup(void) if (!enable_preemption_timer) { vmx_x86_ops.set_hv_timer = NULL; vmx_x86_ops.cancel_hv_timer = NULL; - vmx_x86_ops.request_immediate_exit = __kvm_request_immediate_exit; } kvm_caps.supported_mce_cap |= MCG_LMCE_P; -- cgit v1.2.3