1 files changed, 63 insertions, 119 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 89815a887e4d..fb2bc9f5fe96 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1399,22 +1399,19 @@ int kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val)
 }
 EXPORT_SYMBOL_GPL(kvm_set_dr);
 
-void kvm_get_dr(struct kvm_vcpu *vcpu, int dr, unsigned long *val)
+unsigned long kvm_get_dr(struct kvm_vcpu *vcpu, int dr)
 {
 	size_t size = ARRAY_SIZE(vcpu->arch.db);
 
 	switch (dr) {
 	case 0 ... 3:
-		*val = vcpu->arch.db[array_index_nospec(dr, size)];
-		break;
+		return vcpu->arch.db[array_index_nospec(dr, size)];
 	case 4:
 	case 6:
-		*val = vcpu->arch.dr6;
-		break;
+		return vcpu->arch.dr6;
 	case 5:
 	default: /* 7 */
-		*val = vcpu->arch.dr7;
-		break;
+		return vcpu->arch.dr7;
 	}
 }
 EXPORT_SYMBOL_GPL(kvm_get_dr);
@@ -1704,22 +1701,17 @@ static int do_get_msr_feature(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
 	struct kvm_msr_entry msr;
 	int r;
 
+	/* Unconditionally clear the output for simplicity */
+	msr.data = 0;
 	msr.index = index;
 	r = kvm_get_msr_feature(&msr);
 
-	if (r == KVM_MSR_RET_INVALID) {
-		/* Unconditionally clear the output for simplicity */
-		*data = 0;
-		if (kvm_msr_ignored_check(index, 0, false))
-			r = 0;
-	}
-
-	if (r)
-		return r;
+	if (r == KVM_MSR_RET_INVALID && kvm_msr_ignored_check(index, 0, false))
+		r = 0;
 
 	*data = msr.data;
 
-	return 0;
+	return r;
 }
 
 static bool __kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer)
@@ -2511,7 +2503,7 @@ static u64 compute_guest_tsc(struct kvm_vcpu *vcpu, s64 kernel_ns)
 }
 
 #ifdef CONFIG_X86_64
-static inline int gtod_is_based_on_tsc(int mode)
+static inline bool gtod_is_based_on_tsc(int mode)
 {
 	return mode == VDSO_CLOCKMODE_TSC || mode == VDSO_CLOCKMODE_HVCLOCK;
 }
@@ -4636,7 +4628,7 @@ static bool kvm_is_vm_type_supported(unsigned long type)
 {
 	return type == KVM_X86_DEFAULT_VM ||
 	       (type == KVM_X86_SW_PROTECTED_VM &&
-		IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled);
+		IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_mmu_enabled);
 }
 
 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
@@ -5118,8 +5110,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 	int idx;
 
 	if (vcpu->preempted) {
-		if (!vcpu->arch.guest_state_protected)
-			vcpu->arch.preempted_in_kernel = !static_call(kvm_x86_get_cpl)(vcpu);
+		vcpu->arch.preempted_in_kernel = kvm_arch_vcpu_in_kernel(vcpu);
 
 		/*
 		 * Take the srcu lock as memslots will be accessed to check the gfn
@@ -5510,7 +5501,8 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
 	if (events->flags & KVM_VCPUEVENT_VALID_NMI_PENDING) {
 		vcpu->arch.nmi_pending = 0;
 		atomic_set(&vcpu->arch.nmi_queued, events->nmi.pending);
-		kvm_make_request(KVM_REQ_NMI, vcpu);
+		if (events->nmi.pending)
+			kvm_make_request(KVM_REQ_NMI, vcpu);
 	}
 	static_call(kvm_x86_set_nmi_mask)(vcpu, events->nmi.masked);
 
@@ -5565,18 +5557,23 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
 static void kvm_vcpu_ioctl_x86_get_debugregs(struct kvm_vcpu *vcpu,
 					     struct kvm_debugregs *dbgregs)
 {
-	unsigned long val;
+	unsigned int i;
 
 	memset(dbgregs, 0, sizeof(*dbgregs));
-	memcpy(dbgregs->db, vcpu->arch.db, sizeof(vcpu->arch.db));
-	kvm_get_dr(vcpu, 6, &val);
-	dbgregs->dr6 = val;
+
+	BUILD_BUG_ON(ARRAY_SIZE(vcpu->arch.db) != ARRAY_SIZE(dbgregs->db));
+	for (i = 0; i < ARRAY_SIZE(vcpu->arch.db); i++)
+		dbgregs->db[i] = vcpu->arch.db[i];
+
+	dbgregs->dr6 = vcpu->arch.dr6;
 	dbgregs->dr7 = vcpu->arch.dr7;
 }
 
 static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu,
 					    struct kvm_debugregs *dbgregs)
 {
+	unsigned int i;
+
 	if (dbgregs->flags)
 		return -EINVAL;
 
@@ -5585,7 +5582,9 @@ static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu,
 	if (!kvm_dr7_valid(dbgregs->dr7))
 		return -EINVAL;
 
-	memcpy(vcpu->arch.db, dbgregs->db, sizeof(vcpu->arch.db));
+	for (i = 0; i < ARRAY_SIZE(vcpu->arch.db); i++)
+		vcpu->arch.db[i] = dbgregs->db[i];
+
 	kvm_update_dr0123(vcpu);
 	vcpu->arch.dr6 = dbgregs->dr6;
 	vcpu->arch.dr7 = dbgregs->dr7;
@@ -8223,10 +8222,9 @@ static void emulator_wbinvd(struct x86_emulate_ctxt *ctxt)
 	kvm_emulate_wbinvd_noskip(emul_to_vcpu(ctxt));
 }
 
-static void emulator_get_dr(struct x86_emulate_ctxt *ctxt, int dr,
-			    unsigned long *dest)
+static unsigned long emulator_get_dr(struct x86_emulate_ctxt *ctxt, int dr)
 {
-	kvm_get_dr(emul_to_vcpu(ctxt), dr, dest);
+	return kvm_get_dr(emul_to_vcpu(ctxt), dr);
 }
 
 static int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr,
@@ -8448,12 +8446,9 @@ static int emulator_get_msr(struct x86_emulate_ctxt *ctxt,
 	return kvm_get_msr(emul_to_vcpu(ctxt), msr_index, pdata);
 }
 
-static int emulator_check_pmc(struct x86_emulate_ctxt *ctxt,
-			      u32 pmc)
+static int emulator_check_rdpmc_early(struct x86_emulate_ctxt *ctxt, u32 pmc)
 {
-	if (kvm_pmu_is_valid_rdpmc_ecx(emul_to_vcpu(ctxt), pmc))
-		return 0;
-	return -EINVAL;
+	return kvm_pmu_check_rdpmc_early(emul_to_vcpu(ctxt), pmc);
 }
 
 static int emulator_read_pmc(struct x86_emulate_ctxt *ctxt,
@@ -8585,7 +8580,7 @@ static const struct x86_emulate_ops emulate_ops = {
 	.set_msr_with_filter = emulator_set_msr_with_filter,
 	.get_msr_with_filter = emulator_get_msr_with_filter,
 	.get_msr             = emulator_get_msr,
-	.check_pmc	     = emulator_check_pmc,
+	.check_rdpmc_early   = emulator_check_rdpmc_early,
 	.read_pmc            = emulator_read_pmc,
 	.halt                = emulator_halt,
 	.wbinvd              = emulator_wbinvd,
@@ -8846,31 +8841,24 @@ static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
 
 	kvm_release_pfn_clean(pfn);
 
-	/* The instructions are well-emulated on direct mmu. */
-	if (vcpu->arch.mmu->root_role.direct) {
-		unsigned int indirect_shadow_pages;
-
-		write_lock(&vcpu->kvm->mmu_lock);
-		indirect_shadow_pages = vcpu->kvm->arch.indirect_shadow_pages;
-		write_unlock(&vcpu->kvm->mmu_lock);
-
-		if (indirect_shadow_pages)
-			kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa));
-
-		return true;
-	}
-
 	/*
-	 * if emulation was due to access to shadowed page table
-	 * and it failed try to unshadow page and re-enter the
-	 * guest to let CPU execute the instruction.
+	 * If emulation may have been triggered by a write to a shadowed page
+	 * table, unprotect the gfn (zap any relevant SPTEs) and re-enter the
+	 * guest to let the CPU re-execute the instruction in the hope that the
+	 * CPU can cleanly execute the instruction that KVM failed to emulate.
 	 */
-	kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa));
+	if (vcpu->kvm->arch.indirect_shadow_pages)
+		kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa));
 
 	/*
-	 * If the access faults on its page table, it can not
-	 * be fixed by unprotecting shadow page and it should
-	 * be reported to userspace.
+	 * If the failed instruction faulted on an access to page tables that
+	 * are used to translate any part of the instruction, KVM can't resolve
+	 * the issue by unprotecting the gfn, as zapping the shadow page will
+	 * result in the instruction taking a !PRESENT page fault and thus put
+	 * the vCPU into an infinite loop of page faults.  E.g. KVM will create
+	 * a SPTE and write-protect the gfn to resolve the !PRESENT fault, and
+	 * then zap the SPTE to unprotect the gfn, and then do it all over
+	 * again.  Report the error to userspace.
 	 */
 	return !(emulation_type & EMULTYPE_WRITE_PF_TO_SP);
 }
@@ -8965,7 +8953,7 @@ int kvm_skip_emulated_instruction(struct kvm_vcpu *vcpu)
 	if (unlikely(!r))
 		return 0;
 
-	kvm_pmu_trigger_event(vcpu, PERF_COUNT_HW_INSTRUCTIONS);
+	kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.INSTRUCTIONS_RETIRED);
 
 	/*
 	 * rflags is the old, "raw" value of the flags.  The new value has
@@ -9278,9 +9266,9 @@ writeback:
 		 */
 		if (!ctxt->have_exception ||
 		    exception_type(ctxt->exception.vector) == EXCPT_TRAP) {
-			kvm_pmu_trigger_event(vcpu, PERF_COUNT_HW_INSTRUCTIONS);
+			kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.INSTRUCTIONS_RETIRED);
 			if (ctxt->is_branch)
-				kvm_pmu_trigger_event(vcpu, PERF_COUNT_HW_BRANCH_INSTRUCTIONS);
+				kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.BRANCH_INSTRUCTIONS_RETIRED);
 			kvm_rip_write(vcpu, ctxt->eip);
 			if (r && (ctxt->tf || (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)))
 				r = kvm_vcpu_do_singlestep(vcpu);
@@ -9691,11 +9679,13 @@ static void kvm_x86_check_cpu_compat(void *ret)
 	*(int *)ret = kvm_x86_check_processor_compatibility();
 }
 
-static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
+int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
 {
 	u64 host_pat;
 	int r, cpu;
 
+	guard(mutex)(&vendor_module_lock);
+
 	if (kvm_x86_ops.hardware_enable) {
 		pr_err("already loaded vendor module '%s'\n", kvm_x86_ops.name);
 		return -EEXIST;
@@ -9825,17 +9815,6 @@ out_free_x86_emulator_cache:
 	kmem_cache_destroy(x86_emulator_cache);
 	return r;
 }
-
-int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
-{
-	int r;
-
-	mutex_lock(&vendor_module_lock);
-	r = __kvm_x86_vendor_init(ops);
-	mutex_unlock(&vendor_module_lock);
-
-	return r;
-}
 EXPORT_SYMBOL_GPL(kvm_x86_vendor_init);
 
 void kvm_x86_vendor_exit(void)
@@ -10732,12 +10711,6 @@ static void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu)
 	static_call_cond(kvm_x86_set_apic_access_page_addr)(vcpu);
 }
 
-void __kvm_request_immediate_exit(struct kvm_vcpu *vcpu)
-{
-	smp_send_reschedule(vcpu->cpu);
-}
-EXPORT_SYMBOL_GPL(__kvm_request_immediate_exit);
-
 /*
  * Called within kvm->srcu read side.
  * Returns 1 to let vcpu_run() continue the guest execution loop without
@@ -10987,10 +10960,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 		goto cancel_injection;
 	}
 
-	if (req_immediate_exit) {
+	if (req_immediate_exit)
 		kvm_make_request(KVM_REQ_EVENT, vcpu);
-		static_call(kvm_x86_request_immediate_exit)(vcpu);
-	}
 
 	fpregs_assert_state_consistent();
 	if (test_thread_flag(TIF_NEED_FPU_LOAD))
@@ -11021,7 +10992,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 		WARN_ON_ONCE((kvm_vcpu_apicv_activated(vcpu) != kvm_vcpu_apicv_active(vcpu)) &&
 			     (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED));
 
-		exit_fastpath = static_call(kvm_x86_vcpu_run)(vcpu);
+		exit_fastpath = static_call(kvm_x86_vcpu_run)(vcpu, req_immediate_exit);
 		if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST))
 			break;
 
@@ -12119,27 +12090,9 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 	if (r < 0)
 		return r;
 
-	if (irqchip_in_kernel(vcpu->kvm)) {
-		r = kvm_create_lapic(vcpu, lapic_timer_advance_ns);
-		if (r < 0)
-			goto fail_mmu_destroy;
-
-		/*
-		 * Defer evaluating inhibits until the vCPU is first run, as
-		 * this vCPU will not get notified of any changes until this
-		 * vCPU is visible to other vCPUs (marked online and added to
-		 * the set of vCPUs).  Opportunistically mark APICv active as
-		 * VMX in particularly is highly unlikely to have inhibits.
-		 * Ignore the current per-VM APICv state so that vCPU creation
-		 * is guaranteed to run with a deterministic value, the request
-		 * will ensure the vCPU gets the correct state before VM-Entry.
-		 */
-		if (enable_apicv) {
-			vcpu->arch.apic->apicv_active = true;
-			kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);
-		}
-	} else
-		static_branch_inc(&kvm_has_noapic_vcpu);
+	r = kvm_create_lapic(vcpu, lapic_timer_advance_ns);
+	if (r < 0)
+		goto fail_mmu_destroy;
 
 	r = -ENOMEM;
 
@@ -12260,8 +12213,6 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 	srcu_read_unlock(&vcpu->kvm->srcu, idx);
 	free_page((unsigned long)vcpu->arch.pio_data);
 	kvfree(vcpu->arch.cpuid_entries);
-	if (!lapic_in_kernel(vcpu))
-		static_branch_dec(&kvm_has_noapic_vcpu);
 }
 
 void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
@@ -12538,9 +12489,6 @@ bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
 	return (vcpu->arch.apic_base & MSR_IA32_APICBASE_BSP) != 0;
 }
 
-__read_mostly DEFINE_STATIC_KEY_FALSE(kvm_has_noapic_vcpu);
-EXPORT_SYMBOL_GPL(kvm_has_noapic_vcpu);
-
 void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu)
 {
 	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
@@ -13143,11 +13091,13 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
 
 bool kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu *vcpu)
 {
-	if (kvm_vcpu_apicv_active(vcpu) &&
-	    static_call(kvm_x86_dy_apicv_has_pending_interrupt)(vcpu))
-		return true;
+	return kvm_vcpu_apicv_active(vcpu) &&
+	       static_call(kvm_x86_dy_apicv_has_pending_interrupt)(vcpu);
+}
 
-	return false;
+bool kvm_arch_vcpu_preempted_in_kernel(struct kvm_vcpu *vcpu)
+{
+	return vcpu->arch.preempted_in_kernel;
 }
 
 bool kvm_arch_dy_runnable(struct kvm_vcpu *vcpu)
@@ -13170,9 +13120,6 @@ bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
 	if (vcpu->arch.guest_state_protected)
 		return true;
 
-	if (vcpu != kvm_get_running_vcpu())
-		return vcpu->arch.preempted_in_kernel;
-
 	return static_call(kvm_x86_get_cpl)(vcpu) == 0;
 }
 
@@ -13967,9 +13914,6 @@ module_init(kvm_x86_init);
 
 static void __exit kvm_x86_exit(void)
 {
-	/*
-	 * If module_init() is implemented, module_exit() must also be
-	 * implemented to allow module unload.
-	 */
+	WARN_ON_ONCE(static_branch_unlikely(&kvm_has_noapic_vcpu));
 }
 module_exit(kvm_x86_exit);