Merge branch 'linus' into x86/cleanups, to pick up dependent commits

Signed-off-by: Ingo Molnar <mingo@kernel.org>

62 files changed, 859 insertions, 390 deletions

diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index 22d077562149..7fcb2fd38f42 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -4803,7 +4803,7 @@ KVM_PV_VM_VERIFY
 4.126 KVM_X86_SET_MSR_FILTER
 ----------------------------
 
-:Capability: KVM_X86_SET_MSR_FILTER
+:Capability: KVM_CAP_X86_MSR_FILTER
 :Architectures: x86
 :Type: vm ioctl
 :Parameters: struct kvm_msr_filter
@@ -6715,7 +6715,7 @@ accesses that would usually trigger a #GP by KVM into the guest will
 instead get bounced to user space through the KVM_EXIT_X86_RDMSR and
 KVM_EXIT_X86_WRMSR exit notifications.
 
-8.27 KVM_X86_SET_MSR_FILTER
+8.27 KVM_CAP_X86_MSR_FILTER
 ---------------------------
 
 :Architectures: x86
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index cbbcee0a84f9..55efbacfc244 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -113,6 +113,7 @@
 #define VALID_PAGE(x) ((x) != INVALID_PAGE)
 
 #define UNMAPPED_GVA (~(gpa_t)0)
+#define INVALID_GPA (~(gpa_t)0)
 
 /* KVM Hugepage definitions for x86 */
 #define KVM_MAX_HUGEPAGE_LEVEL	PG_LEVEL_1G
@@ -199,6 +200,7 @@ enum x86_intercept_stage;
 
 #define KVM_NR_DB_REGS	4
 
+#define DR6_BUS_LOCK   (1 << 11)
 #define DR6_BD		(1 << 13)
 #define DR6_BS		(1 << 14)
 #define DR6_BT		(1 << 15)
@@ -212,7 +214,7 @@ enum x86_intercept_stage;
  * DR6_ACTIVE_LOW is also used as the init/reset value for DR6.
  */
 #define DR6_ACTIVE_LOW	0xffff0ff0
-#define DR6_VOLATILE	0x0001e00f
+#define DR6_VOLATILE	0x0001e80f
 #define DR6_FIXED_1	(DR6_ACTIVE_LOW & ~DR6_VOLATILE)
 
 #define DR7_BP_EN_MASK	0x000000ff
@@ -407,7 +409,7 @@ struct kvm_mmu {
 	u32 pkru_mask;
 
 	u64 *pae_root;
-	u64 *lm_root;
+	u64 *pml4_root;
 
 	/*
 	 * check zero bits on shadow page table entries, these
@@ -1417,6 +1419,7 @@ struct kvm_arch_async_pf {
 	bool direct_map;
 };
 
+extern u32 __read_mostly kvm_nr_uret_msrs;
 extern u64 __read_mostly host_efer;
 extern bool __read_mostly allow_smaller_maxphyaddr;
 extern struct kvm_x86_ops kvm_x86_ops;
@@ -1775,9 +1778,15 @@ int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low,
 		    unsigned long ipi_bitmap_high, u32 min,
 		    unsigned long icr, int op_64_bit);
 
-void kvm_define_user_return_msr(unsigned index, u32 msr);
+int kvm_add_user_return_msr(u32 msr);
+int kvm_find_user_return_msr(u32 msr);
 int kvm_set_user_return_msr(unsigned index, u64 val, u64 mask);
 
+static inline bool kvm_is_supported_user_return_msr(u32 msr)
+{
+	return kvm_find_user_return_msr(msr) >= 0;
+}
+
 u64 kvm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc);
 u64 kvm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc);
 
diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h
index 338119852512..69299878b200 100644
--- a/arch/x86/include/asm/kvm_para.h
+++ b/arch/x86/include/asm/kvm_para.h
@@ -7,8 +7,6 @@
 #include <linux/interrupt.h>
 #include <uapi/asm/kvm_para.h>
 
-extern void kvmclock_init(void);
-
 #ifdef CONFIG_KVM_GUEST
 bool kvm_check_and_clear_guest_paused(void);
 #else
@@ -86,13 +84,14 @@ static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
 }
 
 #ifdef CONFIG_KVM_GUEST
+void kvmclock_init(void);
+void kvmclock_disable(void);
 bool kvm_para_available(void);
 unsigned int kvm_arch_para_features(void);
 unsigned int kvm_arch_para_hints(void);
 void kvm_async_pf_task_wait_schedule(u32 token);
 void kvm_async_pf_task_wake(u32 token);
 u32 kvm_read_and_reset_apf_flags(void);
-void kvm_disable_steal_time(void);
 bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token);
 
 DECLARE_STATIC_KEY_FALSE(kvm_async_pf_enabled);
@@ -137,11 +136,6 @@ static inline u32 kvm_read_and_reset_apf_flags(void)
 	return 0;
 }
 
-static inline void kvm_disable_steal_time(void)
-{
-	return;
-}
-
 static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token)
 {
 	return false;
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 5a3022c8af82..0662f644aad9 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -437,6 +437,8 @@ struct kvm_vmx_nested_state_hdr {
 		__u16 flags;
 	} smm;
 
+	__u16 pad;
+
 	__u32 flags;
 	__u64 preemption_timer_deadline;
 };
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index d307c22e5c18..a26643dc6bd6 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -26,6 +26,7 @@
 #include <linux/kprobes.h>
 #include <linux/nmi.h>
 #include <linux/swait.h>
+#include <linux/syscore_ops.h>
 #include <asm/timer.h>
 #include <asm/cpu.h>
 #include <asm/traps.h>
@@ -37,6 +38,7 @@
 #include <asm/tlb.h>
 #include <asm/cpuidle_haltpoll.h>
 #include <asm/ptrace.h>
+#include <asm/reboot.h>
 #include <asm/svm.h>
 
 DEFINE_STATIC_KEY_FALSE(kvm_async_pf_enabled);
@@ -345,7 +347,7 @@ static void kvm_guest_cpu_init(void)
 
 		wrmsrl(MSR_KVM_ASYNC_PF_EN, pa);
 		__this_cpu_write(apf_reason.enabled, 1);
-		pr_info("KVM setup async PF for cpu %d\n", smp_processor_id());
+		pr_info("setup async PF for cpu %d\n", smp_processor_id());
 	}
 
 	if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) {
@@ -371,34 +373,17 @@ static void kvm_pv_disable_apf(void)
 	wrmsrl(MSR_KVM_ASYNC_PF_EN, 0);
 	__this_cpu_write(apf_reason.enabled, 0);
 
-	pr_info("Unregister pv shared memory for cpu %d\n", smp_processor_id());
+	pr_info("disable async PF for cpu %d\n", smp_processor_id());
 }
 
-static void kvm_pv_guest_cpu_reboot(void *unused)
+static void kvm_disable_steal_time(void)
 {
-	/*
-	 * We disable PV EOI before we load a new kernel by kexec,
-	 * since MSR_KVM_PV_EOI_EN stores a pointer into old kernel's memory.
-	 * New kernel can re-enable when it boots.
-	 */
-	if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
-		wrmsrl(MSR_KVM_PV_EOI_EN, 0);
-	kvm_pv_disable_apf();
-	kvm_disable_steal_time();
-}
+	if (!has_steal_clock)
+		return;
 
-static int kvm_pv_reboot_notify(struct notifier_block *nb,
-				unsigned long code, void *unused)
-{
-	if (code == SYS_RESTART)
-		on_each_cpu(kvm_pv_guest_cpu_reboot, NULL, 1);
-	return NOTIFY_DONE;
+	wrmsr(MSR_KVM_STEAL_TIME, 0, 0);
 }
 
-static struct notifier_block kvm_pv_reboot_nb = {
-	.notifier_call = kvm_pv_reboot_notify,
-};
-
 static u64 kvm_steal_clock(int cpu)
 {
 	u64 steal;
@@ -416,14 +401,6 @@ static u64 kvm_steal_clock(int cpu)
 	return steal;
 }
 
-void kvm_disable_steal_time(void)
-{
-	if (!has_steal_clock)
-		return;
-
-	wrmsr(MSR_KVM_STEAL_TIME, 0, 0);
-}
-
 static inline void __set_percpu_decrypted(void *ptr, unsigned long size)
 {
 	early_set_memory_decrypted((unsigned long) ptr, size);
@@ -451,6 +428,27 @@ static void __init sev_map_percpu_data(void)
 	}
 }
 
+static void kvm_guest_cpu_offline(bool shutdown)
+{
+	kvm_disable_steal_time();
+	if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
+		wrmsrl(MSR_KVM_PV_EOI_EN, 0);
+	kvm_pv_disable_apf();
+	if (!shutdown)
+		apf_task_wake_all();
+	kvmclock_disable();
+}
+
+static int kvm_cpu_online(unsigned int cpu)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	kvm_guest_cpu_init();
+	local_irq_restore(flags);
+	return 0;
+}
+
 #ifdef CONFIG_SMP
 
 static DEFINE_PER_CPU(cpumask_var_t, __pv_cpu_mask);
@@ -635,31 +633,64 @@ static void __init kvm_smp_prepare_boot_cpu(void)
 	kvm_spinlock_init();
 }
 
-static void kvm_guest_cpu_offline(void)
+static int kvm_cpu_down_prepare(unsigned int cpu)
 {
-	kvm_disable_steal_time();
-	if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
-		wrmsrl(MSR_KVM_PV_EOI_EN, 0);
-	kvm_pv_disable_apf();
-	apf_task_wake_all();
+	unsigned long flags;
+
+	local_irq_save(flags);
+	kvm_guest_cpu_offline(false);
+	local_irq_restore(flags);
+	return 0;
 }
 
-static int kvm_cpu_online(unsigned int cpu)
+#endif
+
+static int kvm_suspend(void)
 {
-	local_irq_disable();
-	kvm_guest_cpu_init();
-	local_irq_enable();
+	kvm_guest_cpu_offline(false);
+
 	return 0;
 }
 
-static int kvm_cpu_down_prepare(unsigned int cpu)
+static void kvm_resume(void)
 {
-	local_irq_disable();
-	kvm_guest_cpu_offline();
-	local_irq_enable();
-	return 0;
+	kvm_cpu_online(raw_smp_processor_id());
+}
+
+static struct syscore_ops kvm_syscore_ops = {
+	.suspend	= kvm_suspend,
+	.resume		= kvm_resume,
+};
+
+static void kvm_pv_guest_cpu_reboot(void *unused)
+{
+	kvm_guest_cpu_offline(true);
+}
+
+static int kvm_pv_reboot_notify(struct notifier_block *nb,
+				unsigned long code, void *unused)
+{
+	if (code == SYS_RESTART)
+		on_each_cpu(kvm_pv_guest_cpu_reboot, NULL, 1);
+	return NOTIFY_DONE;
 }
 
+static struct notifier_block kvm_pv_reboot_nb = {
+	.notifier_call = kvm_pv_reboot_notify,
+};
+
+/*
+ * After a PV feature is registered, the host will keep writing to the
+ * registered memory location. If the guest happens to shutdown, this memory
+ * won't be valid. In cases like kexec, in which you install a new kernel, this
+ * means a random memory location will be kept being written.
+ */
+#ifdef CONFIG_KEXEC_CORE
+static void kvm_crash_shutdown(struct pt_regs *regs)
+{
+	kvm_guest_cpu_offline(true);
+	native_machine_crash_shutdown(regs);
+}
 #endif
 
 static void __init kvm_guest_init(void)
@@ -704,6 +735,12 @@ static void __init kvm_guest_init(void)
 	kvm_guest_cpu_init();
 #endif
 
+#ifdef CONFIG_KEXEC_CORE
+	machine_ops.crash_shutdown = kvm_crash_shutdown;
+#endif
+
+	register_syscore_ops(&kvm_syscore_ops);
+
 	/*
 	 * Hard lockup detection is enabled by default. Disable it, as guests
 	 * can get false positives too easily, for example if the host is
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index d37ed4e1d033..ad273e5861c1 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -20,7 +20,6 @@
 #include <asm/hypervisor.h>
 #include <asm/mem_encrypt.h>
 #include <asm/x86_init.h>
-#include <asm/reboot.h>
 #include <asm/kvmclock.h>
 
 static int kvmclock __initdata = 1;
@@ -203,28 +202,9 @@ static void kvm_setup_secondary_clock(void)
 }
 #endif
 
-/*
- * After the clock is registered, the host will keep writing to the
- * registered memory location. If the guest happens to shutdown, this memory
- * won't be valid. In cases like kexec, in which you install a new kernel, this
- * means a random memory location will be kept being written. So before any
- * kind of shutdown from our side, we unregister the clock by writing anything
- * that does not have the 'enable' bit set in the msr
- */
-#ifdef CONFIG_KEXEC_CORE
-static void kvm_crash_shutdown(struct pt_regs *regs)
-{
-	native_write_msr(msr_kvm_system_time, 0, 0);
-	kvm_disable_steal_time();
-	native_machine_crash_shutdown(regs);
-}
-#endif
-
-static void kvm_shutdown(void)
+void kvmclock_disable(void)
 {
 	native_write_msr(msr_kvm_system_time, 0, 0);
-	kvm_disable_steal_time();
-	native_machine_shutdown();
 }
 
 static void __init kvmclock_init_mem(void)
@@ -351,10 +331,6 @@ void __init kvmclock_init(void)
 #endif
 	x86_platform.save_sched_clock_state = kvm_save_sched_clock_state;
 	x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state;
-	machine_ops.shutdown  = kvm_shutdown;
-#ifdef CONFIG_KEXEC_CORE
-	machine_ops.crash_shutdown  = kvm_crash_shutdown;
-#endif
 	kvm_get_preset_lpj();
 
 	/*
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 19606a341888..9a48f138832d 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -458,7 +458,7 @@ void kvm_set_cpu_caps(void)
 		F(AVX512_VPOPCNTDQ) | F(UMIP) | F(AVX512_VBMI2) | F(GFNI) |
 		F(VAES) | F(VPCLMULQDQ) | F(AVX512_VNNI) | F(AVX512_BITALG) |
 		F(CLDEMOTE) | F(MOVDIRI) | F(MOVDIR64B) | 0 /*WAITPKG*/ |
-		F(SGX_LC)
+		F(SGX_LC) | F(BUS_LOCK_DETECT)
 	);
 	/* Set LA57 based on hardware capability. */
 	if (cpuid_ecx(7) & F(LA57))
@@ -567,6 +567,21 @@ void kvm_set_cpu_caps(void)
 		F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
 		F(PMM) | F(PMM_EN)
 	);
+
+	/*
+	 * Hide RDTSCP and RDPID if either feature is reported as supported but
+	 * probing MSR_TSC_AUX failed.  This is purely a sanity check and
+	 * should never happen, but the guest will likely crash if RDTSCP or
+	 * RDPID is misreported, and KVM has botched MSR_TSC_AUX emulation in
+	 * the past.  For example, the sanity check may fire if this instance of
+	 * KVM is running as L1 on top of an older, broken KVM.
+	 */
+	if (WARN_ON((kvm_cpu_cap_has(X86_FEATURE_RDTSCP) ||
+		     kvm_cpu_cap_has(X86_FEATURE_RDPID)) &&
+		     !kvm_is_supported_user_return_msr(MSR_TSC_AUX))) {
+		kvm_cpu_cap_clear(X86_FEATURE_RDTSCP);
+		kvm_cpu_cap_clear(X86_FEATURE_RDPID);
+	}
 }
 EXPORT_SYMBOL_GPL(kvm_set_cpu_caps);
 
@@ -637,7 +652,8 @@ static int __do_cpuid_func_emulated(struct kvm_cpuid_array *array, u32 func)
 	case 7:
 		entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
 		entry->eax = 0;
-		entry->ecx = F(RDPID);
+		if (kvm_cpu_cap_has(X86_FEATURE_RDTSCP))
+			entry->ecx = F(RDPID);
 		++array->nent;
 	default:
 		break;
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 77e1c89a95a7..8a0ccdb56076 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -4502,7 +4502,7 @@ static const struct opcode group8[] = {
  * from the register case of group9.
  */
 static const struct gprefix pfx_0f_c7_7 = {
-	N, N, N, II(DstMem | ModRM | Op3264 | EmulateOnUD, em_rdpid, rdtscp),
+	N, N, N, II(DstMem | ModRM | Op3264 | EmulateOnUD, em_rdpid, rdpid),
 };
 
 
diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h
index 0d359115429a..f016838faedd 100644
--- a/arch/x86/kvm/kvm_emulate.h
+++ b/arch/x86/kvm/kvm_emulate.h
@@ -468,6 +468,7 @@ enum x86_intercept {
 	x86_intercept_clgi,
 	x86_intercept_skinit,
 	x86_intercept_rdtscp,
+	x86_intercept_rdpid,
 	x86_intercept_icebp,
 	x86_intercept_wbinvd,
 	x86_intercept_monitor,
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 152591f9243a..c0ebef560bd1 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1913,8 +1913,8 @@ void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu)
 	if (!apic->lapic_timer.hv_timer_in_use)
 		goto out;
 	WARN_ON(rcuwait_active(&vcpu->wait));
-	cancel_hv_timer(apic);
 	apic_timer_expired(apic, false);
+	cancel_hv_timer(apic);
 
 	if (apic_lvtt_period(apic) && apic->lapic_timer.period) {
 		advance_periodic_target_expiration(apic);
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 4b3ee244ebe0..0144c40d09c7 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3310,12 +3310,12 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu)
 	if (mmu->shadow_root_level == PT64_ROOT_4LEVEL) {
 		pm_mask |= PT_ACCESSED_MASK | PT_WRITABLE_MASK | PT_USER_MASK;
 
-		if (WARN_ON_ONCE(!mmu->lm_root)) {
+		if (WARN_ON_ONCE(!mmu->pml4_root)) {
 			r = -EIO;
 			goto out_unlock;
 		}
 
-		mmu->lm_root[0] = __pa(mmu->pae_root) | pm_mask;
+		mmu->pml4_root[0] = __pa(mmu->pae_root) | pm_mask;
 	}
 
 	for (i = 0; i < 4; ++i) {
@@ -3335,7 +3335,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu)
 	}
 
 	if (mmu->shadow_root_level == PT64_ROOT_4LEVEL)
-		mmu->root_hpa = __pa(mmu->lm_root);
+		mmu->root_hpa = __pa(mmu->pml4_root);
 	else
 		mmu->root_hpa = __pa(mmu->pae_root);
 
@@ -3350,7 +3350,7 @@ out_unlock:
 static int mmu_alloc_special_roots(struct kvm_vcpu *vcpu)
 {
 	struct kvm_mmu *mmu = vcpu->arch.mmu;
-	u64 *lm_root, *pae_root;
+	u64 *pml4_root, *pae_root;
 
 	/*
 	 * When shadowing 32-bit or PAE NPT with 64-bit NPT, the PML4 and PDP
@@ -3369,14 +3369,14 @@ static int mmu_alloc_special_roots(struct kvm_vcpu *vcpu)
 	if (WARN_ON_ONCE(mmu->shadow_root_level != PT64_ROOT_4LEVEL))
 		return -EIO;
 
-	if (mmu->pae_root && mmu->lm_root)
+	if (mmu->pae_root && mmu->pml4_root)
 		return 0;
 
 	/*
 	 * The special roots should always be allocated in concert.  Yell and
 	 * bail if KVM ends up in a state where only one of the roots is valid.
 	 */
-	if (WARN_ON_ONCE(!tdp_enabled || mmu->pae_root || mmu->lm_root))
+	if (WARN_ON_ONCE(!tdp_enabled || mmu->pae_root || mmu->pml4_root))
 		return -EIO;
 
 	/*
@@ -3387,14 +3387,14 @@ static int mmu_alloc_special_roots(struct kvm_vcpu *vcpu)
 	if (!pae_root)
 		return -ENOMEM;
 
-	lm_root = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);
-	if (!lm_root) {
+	pml4_root = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);
+	if (!pml4_root) {
 		free_page((unsigned long)pae_root);
 		return -ENOMEM;
 	}
 
 	mmu->pae_root = pae_root;
-	mmu->lm_root = lm_root;
+	mmu->pml4_root = pml4_root;
 
 	return 0;
 }
@@ -5261,7 +5261,7 @@ static void free_mmu_pages(struct kvm_mmu *mmu)
 	if (!tdp_enabled && mmu->pae_root)
 		set_memory_encrypted((unsigned long)mmu->pae_root, 1);
 	free_page((unsigned long)mmu->pae_root);
-	free_page((unsigned long)mmu->lm_root);
+	free_page((unsigned long)mmu->pml4_root);
 }
 
 static int __kvm_mmu_create(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 88f69a6cc492..95eeb5ac6a8a 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -388,7 +388,7 @@ static void handle_removed_tdp_mmu_page(struct kvm *kvm, tdp_ptep_t pt,
 }
 
 /**
- * handle_changed_spte - handle bookkeeping associated with an SPTE change
+ * __handle_changed_spte - handle bookkeeping associated with an SPTE change
  * @kvm: kvm instance
  * @as_id: the address space of the paging structure the SPTE was a part of
  * @gfn: the base G