diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 83dc5086138b..a4d872ddef9d 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -134,6 +134,7 @@ KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
 KVM_X86_OP_OPTIONAL(vm_copy_enc_context_from)
 KVM_X86_OP_OPTIONAL(vm_move_enc_context_from)
 KVM_X86_OP_OPTIONAL(guest_memory_reclaimed)
+KVM_X86_OP_OPTIONAL(reload_vmsa)
 KVM_X86_OP(get_feature_msr)
 KVM_X86_OP(check_emulate_instruction)
 KVM_X86_OP(apic_init_signal_blocked)
@@ -145,9 +146,16 @@ KVM_X86_OP(vcpu_deliver_sipi_vector)
 KVM_X86_OP_OPTIONAL_RET0(vcpu_get_apicv_inhibit_reasons);
 KVM_X86_OP_OPTIONAL(get_untagged_addr)
 KVM_X86_OP_OPTIONAL(alloc_apic_backing_page)
-KVM_X86_OP_OPTIONAL_RET0(gmem_prepare)
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT
+KVM_X86_OP_OPTIONAL_RET0(gmem_make_private)
+#endif
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_RECLAIM
+KVM_X86_OP_OPTIONAL(gmem_make_shared)
+#endif
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
+KVM_X86_OP_OPTIONAL(gmem_invalidate_range)
+#endif
 KVM_X86_OP_OPTIONAL_RET0(gmem_max_mapping_level)
-KVM_X86_OP_OPTIONAL(gmem_invalidate)
 #endif
 
 #undef KVM_X86_OP
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index eca04d4b974e..d9f5e01091e9 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -122,6 +122,8 @@
 	KVM_ARCH_REQ_FLAGS(31, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
 #define KVM_REQ_HV_TLB_FLUSH \
 	KVM_ARCH_REQ_FLAGS(32, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
+#define KVM_REQ_VMSA_PAGE_RELOAD \
+	KVM_ARCH_REQ_FLAGS(33, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
 #define KVM_REQ_UPDATE_PROTECTED_GUEST_STATE \
 	KVM_ARCH_REQ_FLAGS(34, KVM_REQUEST_WAIT)
 
@@ -1878,6 +1880,7 @@ struct kvm_x86_ops {
 	int (*vm_copy_enc_context_from)(struct kvm *kvm, unsigned int source_fd);
 	int (*vm_move_enc_context_from)(struct kvm *kvm, unsigned int source_fd);
 	void (*guest_memory_reclaimed)(struct kvm *kvm);
+	void (*reload_vmsa)(struct kvm_vcpu *vcpu);
 
 	int (*get_feature_msr)(u32 msr, u64 *data);
 
@@ -1900,8 +1903,16 @@ struct kvm_x86_ops {
 
 	gva_t (*get_untagged_addr)(struct kvm_vcpu *vcpu, gva_t gva, unsigned int flags);
 	void *(*alloc_apic_backing_page)(struct kvm_vcpu *vcpu);
-	int (*gmem_prepare)(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order);
-	void (*gmem_invalidate)(kvm_pfn_t start, kvm_pfn_t end);
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT
+	int (*gmem_make_private)(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn,
+				 kvm_pfn_t nr_pages);
+#endif
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_RECLAIM
+	void (*gmem_make_shared)(kvm_pfn_t pfn, kvm_pfn_t nr_pages);
+#endif
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
+	void (*gmem_invalidate_range)(struct kvm *kvm, struct kvm_gfn_range *range);
+#endif
 	int (*gmem_max_mapping_level)(struct kvm *kvm, kvm_pfn_t pfn, bool is_private);
 };
 
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 801bf9e520db..538ed1e80332 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -160,7 +160,8 @@ config KVM_AMD_SEV
 	depends on CRYPTO_DEV_SP_PSP && !(KVM_AMD=y && CRYPTO_DEV_CCP_DD=m)
 	select ARCH_HAS_CC_PLATFORM
 	select KVM_GENERIC_MEMORY_ATTRIBUTES
-	select HAVE_KVM_ARCH_GMEM_PREPARE
+	select HAVE_KVM_ARCH_GMEM_CONVERT
+	select HAVE_KVM_ARCH_GMEM_RECLAIM
 	select HAVE_KVM_ARCH_GMEM_INVALIDATE
 	select HAVE_KVM_ARCH_GMEM_POPULATE
 	help
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index e7d75f84a8ab..cf206f68af54 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -6947,20 +6947,11 @@ static void kvm_zap_obsolete_pages(struct kvm *kvm)
 	kvm_mmu_commit_zap_page(kvm, &invalid_list);
 }
 
-/*
- * Fast invalidate all shadow pages and use lock-break technique
- * to zap obsolete pages.
- *
- * It's required when memslot is being deleted or VM is being
- * destroyed, in these cases, we should ensure that KVM MMU does
- * not use any resource of the being-deleted slot or all slots
- * after calling the function.
- */
-static void kvm_mmu_zap_all_fast(struct kvm *kvm)
+static void __kvm_mmu_zap_all_fast_front_half(struct kvm *kvm)
 {
 	lockdep_assert_held(&kvm->slots_lock);
+	lockdep_assert_held_write(&kvm->mmu_lock);
 
-	write_lock(&kvm->mmu_lock);
 	trace_kvm_mmu_zap_all_fast(kvm);
 
 	/*
@@ -6997,8 +6988,12 @@ static void kvm_mmu_zap_all_fast(struct kvm *kvm)
 	kvm_make_all_cpus_request(kvm, KVM_REQ_MMU_FREE_OBSOLETE_ROOTS);
 
 	kvm_zap_obsolete_pages(kvm);
+}
 
-	write_unlock(&kvm->mmu_lock);
+static void __kvm_mmu_zap_all_fast_back_half(struct kvm *kvm)
+{
+	lockdep_assert_held(&kvm->slots_lock);
+	lockdep_assert_not_held(&kvm->mmu_lock);
 
 	/*
 	 * Zap the invalidated TDP MMU roots, all SPTEs must be dropped before
@@ -7012,6 +7007,24 @@ static void kvm_mmu_zap_all_fast(struct kvm *kvm)
 		kvm_tdp_mmu_zap_invalidated_roots(kvm, true);
 }
 
+/*
+ * Fast invalidate all shadow pages and use lock-break technique
+ * to zap obsolete pages.
+ *
+ * It's required when memslot is being deleted or VM is being
+ * destroyed, in these cases, we should ensure that KVM MMU does
+ * not use any resource of the being-deleted slot or all slots
+ * after calling the function.
+ */
+static void kvm_mmu_zap_all_fast(struct kvm *kvm)
+{
+	write_lock(&kvm->mmu_lock);
+	__kvm_mmu_zap_all_fast_front_half(kvm);
+	write_unlock(&kvm->mmu_lock);
+
+	__kvm_mmu_zap_all_fast_back_half(kvm);
+}
+
 int kvm_mmu_init_vm(struct kvm *kvm)
 {
 	int r, i;
@@ -7586,8 +7599,8 @@ static void kvm_mmu_zap_memslot_pages_and_flush(struct kvm *kvm,
 	kvm_mmu_remote_flush_or_zap(kvm, &invalid_list, flush);
 }
 
-static void kvm_mmu_zap_memslot(struct kvm *kvm,
-				struct kvm_memory_slot *slot)
+void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
+				   struct kvm_memory_slot *slot)
 {
 	struct kvm_gfn_range range = {
 		.slot = slot,
@@ -7596,27 +7609,28 @@ static void kvm_mmu_zap_memslot(struct kvm *kvm,
 		.may_block = true,
 		.attr_filter = KVM_FILTER_PRIVATE | KVM_FILTER_SHARED,
 	};
+	bool zap_all = kvm->arch.vm_type == KVM_X86_DEFAULT_VM &&
+		       kvm_check_has_quirk(kvm, KVM_X86_QUIRK_SLOT_ZAP_ALL);
 	bool flush;
 
 	write_lock(&kvm->mmu_lock);
-	flush = kvm_unmap_gfn_range(kvm, &range);
-	kvm_mmu_zap_memslot_pages_and_flush(kvm, slot, flush);
+
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
+	if (slot->gmem.file)
+		kvm_arch_gmem_invalidate_range(kvm, &range);
+#endif
+
+	if (zap_all) {
+		__kvm_mmu_zap_all_fast_front_half(kvm);
+	} else {
+		flush = kvm_unmap_gfn_range(kvm, &range);
+		kvm_mmu_zap_memslot_pages_and_flush(kvm, slot, flush);
+	}
+
 	write_unlock(&kvm->mmu_lock);
-}
 
-static inline bool kvm_memslot_flush_zap_all(struct kvm *kvm)
-{
-	return kvm->arch.vm_type == KVM_X86_DEFAULT_VM &&
-	       kvm_check_has_quirk(kvm, KVM_X86_QUIRK_SLOT_ZAP_ALL);
-}
-
-void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
-				   struct kvm_memory_slot *slot)
-{
-	if (kvm_memslot_flush_zap_all(kvm))
-		kvm_mmu_zap_all_fast(kvm);
-	else
-		kvm_mmu_zap_memslot(kvm, slot);
+	if (zap_all)
+		__kvm_mmu_zap_all_fast_back_half(kvm);
 }
 
 void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm, u64 gen)
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 0f0ea7896af5..70be8c384cea 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3998,30 +3998,25 @@ static int snp_begin_psc(struct vcpu_svm *svm)
 	return snp_do_psc(svm);
 }
 
-/*
- * Invoked as part of svm_vcpu_reset() processing of an init event.
- */
-static void sev_snp_init_protected_guest_state(struct kvm_vcpu *vcpu)
+static void __sev_snp_reload_vmsa(struct kvm_vcpu *vcpu, gpa_t gpa)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
 	struct kvm_memory_slot *slot;
+	struct kvm *kvm = vcpu->kvm;
+	gfn_t gfn = gpa_to_gfn(gpa);
+	unsigned long mmu_seq;
 	struct page *page;
 	kvm_pfn_t pfn;
-	gfn_t gfn;
 
-	guard(mutex)(&svm->sev_es.snp_vmsa_mutex);
+	lockdep_assert_held(&svm->sev_es.snp_vmsa_mutex);
 
-	if (!svm->sev_es.snp_ap_waiting_for_reset)
-		return;
-
-	svm->sev_es.snp_ap_waiting_for_reset = false;
-
-	/* Mark the vCPU as offline and not runnable */
-	vcpu->arch.pv.pv_unhalted = false;
-	kvm_set_mp_state(vcpu, KVM_MP_STATE_HALTED);
-
-	/* Clear use of the VMSA */
+	/*
+	 * Clear use of the VMSA.  Ensure snp_guest_vmsa_gpa is written exactly
+	 * once, as it is read locklessly when responding to gfn invalidations.
+	 * Pairs with the READ_ONCE() in sev_gmem_invalidate_range().
+	 */
 	svm->vmcb->control.vmsa_pa = INVALID_PAGE;
+	WRITE_ONCE(svm->sev_es.snp_guest_vmsa_gpa, INVALID_PAGE);
 
 	/*
 	 * When replacing the VMSA during SEV-SNP AP creation,
@@ -4029,23 +4024,6 @@ static void sev_snp_init_protected_guest_state(struct kvm_vcpu *vcpu)
 	 */
 	vmcb_mark_all_dirty(svm->vmcb);
 
-	if (!VALID_PAGE(svm->sev_es.snp_vmsa_gpa))
-		return;
-
-	gfn = gpa_to_gfn(svm->sev_es.snp_vmsa_gpa);
-	svm->sev_es.snp_vmsa_gpa = INVALID_PAGE;
-
-	slot = gfn_to_memslot(vcpu->kvm, gfn);
-	if (!slot)
-		return;
-
-	/*
-	 * The new VMSA will be private memory guest memory, so retrieve the
-	 * PFN from the gmem backend.
-	 */
-	if (kvm_gmem_get_pfn(vcpu->kvm, slot, gfn, &pfn, &page, NULL))
-		return;
-
 	/*
 	 * From this point forward, the VMSA will always be a guest-mapped page
 	 * rather than the initial one allocated by KVM in svm->sev_es.vmsa. In
@@ -4057,20 +4035,83 @@ static void sev_snp_init_protected_guest_state(struct kvm_vcpu *vcpu)
 	 */
 	svm->sev_es.snp_has_guest_vmsa = true;
 
-	/* Use the new VMSA */
-	svm->vmcb->control.vmsa_pa = pfn_to_hpa(pfn);
+	if (!VALID_PAGE(gpa))
+		return;
 
-	/* Mark the vCPU as runnable */
-	kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE);
+	slot = gfn_to_memslot(vcpu->kvm, gfn);
+	if (!slot)
+		return;
+
+	mmu_seq = kvm->mmu_invalidate_seq;
+	smp_rmb();
 
 	/*
-	 * gmem pages aren't currently migratable, but if this ever changes
-	 * then care should be taken to ensure svm->sev_es.vmsa is pinned
-	 * through some other means.
+	 * The new VMSA will be private memory guest memory, so retrieve the
+	 * PFN from the gmem backend.
 	 */
+	if (kvm_gmem_get_pfn(vcpu->kvm, slot, gfn, &pfn, &page, NULL))
+		return;
+
+	read_lock(&kvm->mmu_lock);
+	/*
+	 * Save the guest-provided GPA.  If retry is needed, then KVM will try
+	 * again with the same GPA.  If the VMSA is usable, then KVM needs to
+	 * track the GPA so that the VMSA can be reloaded if the backing page
+	 * for the GPA is invalidated.
+	 */
+	svm->sev_es.snp_guest_vmsa_gpa = gpa;
+	if (mmu_invalidate_retry_gfn(kvm, mmu_seq, gfn))
+		kvm_make_request(KVM_REQ_VMSA_PAGE_RELOAD, vcpu);
+	else
+		svm->vmcb->control.vmsa_pa = pfn_to_hpa(pfn);
+	read_unlock(&kvm->mmu_lock);
+
 	kvm_release_page_clean(page);
 }
 
+/*
+ * Invoked as part of svm_vcpu_reset() processing of an init event.
+ */
+static void sev_snp_init_protected_guest_state(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_svm *svm = to_svm(vcpu);
+	gpa_t gpa;
+
+	guard(mutex)(&svm->sev_es.snp_vmsa_mutex);
+
+	if (!svm->sev_es.snp_ap_waiting_for_reset)
+		return;
+
+	svm->sev_es.snp_ap_waiting_for_reset = false;
+
+	/* Mark the vCPU as offline and not runnable */
+	vcpu->arch.pv.pv_unhalted = false;
+	kvm_set_mp_state(vcpu, KVM_MP_STATE_HALTED);
+
+	gpa = svm->sev_es.snp_pending_vmsa_gpa;
+	svm->sev_es.snp_pending_vmsa_gpa = INVALID_PAGE;
+
+	__sev_snp_reload_vmsa(vcpu, gpa);
+
+	/*
+	 * Mark the vCPU as runnable for CREATE requests, indicated by a valid
+	 * VMSA GPA, even if installing the VMSA failed, so that KVM_RUN will
+	 * fail instead of blocking indefinitely and hanging the vCPU, e.g. if
+	 * the backing guest_memfd page is unavailable.
+	 */
+	if (VALID_PAGE(gpa))
+		kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE);
+}
+
+void sev_snp_reload_vmsa(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_sev_es_state *sev_es = &to_svm(vcpu)->sev_es;
+
+	guard(mutex)(&sev_es->snp_vmsa_mutex);
+
+	__sev_snp_reload_vmsa(vcpu, sev_es->snp_guest_vmsa_gpa);
+}
+
 static int sev_snp_ap_creation(struct vcpu_svm *svm)
 {
 	struct kvm_sev_info *sev = to_kvm_sev_info(svm->vcpu.kvm);
@@ -4124,10 +4165,10 @@ static int sev_snp_ap_creation(struct vcpu_svm *svm)
 			return -EINVAL;
 		}
 
-		target_svm->sev_es.snp_vmsa_gpa = svm->vmcb->control.exit_info_2;
+		target_svm->sev_es.snp_pending_vmsa_gpa = svm->vmcb->control.exit_info_2;
 		break;
 	case SVM_VMGEXIT_AP_DESTROY:
-		target_svm->sev_es.snp_vmsa_gpa = INVALID_PAGE;
+		target_svm->sev_es.snp_pending_vmsa_gpa = INVALID_PAGE;
 		break;
 	default:
 		vcpu_unimpl(vcpu, "vmgexit: invalid AP creation request [%#x] from guest\n",
@@ -4810,6 +4851,8 @@ int sev_vcpu_create(struct kvm_vcpu *vcpu)
 		return -ENOMEM;
 
 	svm->sev_es.vmsa = page_address(vmsa_page);
+	svm->sev_es.snp_pending_vmsa_gpa = INVALID_PAGE;
+	svm->sev_es.snp_guest_vmsa_gpa = INVALID_PAGE;
 
 	vcpu->arch.guest_tsc_protected = snp_is_secure_tsc_enabled(vcpu->kvm);
 
@@ -5064,15 +5107,7 @@ static bool is_pfn_range_shared(kvm_pfn_t start, kvm_pfn_t end)
 	return true;
 }
 
-static u8 max_level_for_order(int order)
-{
-	if (order >= KVM_HPAGE_GFN_SHIFT(PG_LEVEL_2M))
-		return PG_LEVEL_2M;
-
-	return PG_LEVEL_4K;
-}
-
-static bool is_large_rmp_possible(struct kvm *kvm, kvm_pfn_t pfn, int order)
+static bool is_large_rmp_possible(kvm_pfn_t pfn, kvm_pfn_t nr_pages)
 {
 	kvm_pfn_t pfn_aligned = ALIGN_DOWN(pfn, PTRS_PER_PMD);
 
@@ -5081,14 +5116,14 @@ static bool is_large_rmp_possible(struct kvm *kvm, kvm_pfn_t pfn, int order)
 	 * PFN is currently shared, then the entire 2M-aligned range can be
 	 * set to private via a single 2M RMP entry.
 	 */
-	if (max_level_for_order(order) > PG_LEVEL_4K &&
+	if (nr_pages >= KVM_PAGES_PER_HPAGE(PG_LEVEL_2M) &&
 	    is_pfn_range_shared(pfn_aligned, pfn_aligned + PTRS_PER_PMD))
 		return true;
 
 	return false;
 }
 
-int sev_gmem_prepare(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order)
+int sev_gmem_make_private(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, kvm_pfn_t nr_pages)
 {
 	struct kvm_sev_info *sev = to_kvm_sev_info(kvm);
 	kvm_pfn_t pfn_aligned;
@@ -5099,6 +5134,9 @@ int sev_gmem_prepare(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order)
 	if (!sev_snp_guest(kvm))
 		return 0;
 
+	if (WARN_ON_ONCE(nr_pages != 1))
+		return -EIO;
+
 	rc = snp_lookup_rmpentry(pfn, &assigned, &level);
 	if (rc) {
 		pr_err_ratelimited("SEV: Failed to look up RMP entry: GFN %llx PFN %llx error %d\n",
@@ -5107,12 +5145,12 @@ int sev_gmem_prepare(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order)
 	}
 
 	if (assigned) {
-		pr_debug("%s: already assigned: gfn %llx pfn %llx max_order %d level %d\n",
-			 __func__, gfn, pfn, max_order, level);
+		pr_debug("%s: already assigned: gfn %llx pfn %llx nr_pages %llx level %d\n",
+			 __func__, gfn, pfn, nr_pages, level);
 		return 0;
 	}
 
-	if (is_large_rmp_possible(kvm, pfn, max_order)) {
+	if (is_large_rmp_possible(pfn, nr_pages)) {
 		level = PG_LEVEL_2M;
 		pfn_aligned = ALIGN_DOWN(pfn, PTRS_PER_PMD);
 		gfn_aligned = ALIGN_DOWN(gfn, PTRS_PER_PMD);
@@ -5129,22 +5167,22 @@ int sev_gmem_prepare(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order)
 		return -EINVAL;
 	}
 
-	pr_debug("%s: updated: gfn %llx pfn %llx pfn_aligned %llx max_order %d level %d\n",
-		 __func__, gfn, pfn, pfn_aligned, max_order, level);
+	pr_debug("%s: updated: gfn %llx pfn %llx pfn_aligned %llx nr_pages %llx level %d\n",
+		 __func__, gfn, pfn, pfn_aligned, nr_pages, level);
 
 	return 0;
 }
 
-void sev_gmem_invalidate(kvm_pfn_t start, kvm_pfn_t end)
+void sev_gmem_make_shared(kvm_pfn_t pfn, kvm_pfn_t nr_pages)
 {
-	kvm_pfn_t pfn;
+	kvm_pfn_t end = pfn + nr_pages;
 
 	if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
 		return;
 
-	pr_debug("%s: PFN start 0x%llx PFN end 0x%llx\n", __func__, start, end);
+	pr_debug("%s: PFN start 0x%llx PFN end 0x%llx\n", __func__, pfn, end);
 
-	for (pfn = start; pfn < end;) {
+	while (pfn < end) {
 		bool use_2m_update = false;
 		int rc, rmp_level;
 		bool assigned;
@@ -5198,6 +5236,41 @@ void sev_gmem_invalidate(kvm_pfn_t start, kvm_pfn_t end)
 	}
 }
 
+void sev_gmem_invalidate_range(struct kvm *kvm, struct kvm_gfn_range *range)
+{
+	struct kvm_vcpu *vcpu;
+	unsigned long i;
+
+	lockdep_assert_held_write(&kvm->mmu_lock);
+
+	/*
+	 * An unstable result for "is SNP" is a-ok here, thanks to mmu_lock.
+	 * The vCPU's VMSA GPA is invalidated before the vCPU is made visible
+	 * to other tasks, and can only become valid while holding mmu_lock,
+	 * after the VM is fully committed to being an SNP VM.
+	 */
+	if (!____sev_snp_guest(kvm))
+		return;
+
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		/*
+		 * Read snp_guest_vmsa_gpa without taking the vCPU's VMSA mutex
+		 * (or its generic mutex) as mmu_lock is held, i.e. this task
+		 * can't sleep.  The VMSA is invalidated outside of mmu_lock,
+		 * but can only become valid inside of mmu_lock, i.e. the below
+		 * can get false positives, but not false negatives.  A false
+		 * positive is benign, as a spurious request simply forces the
+		 * vCPU to re-establish its VMSA.
+		 */
+		gpa_t gpa = READ_ONCE(to_svm(vcpu)->sev_es.snp_guest_vmsa_gpa);
+
+		if (VALID_PAGE(gpa) &&
+		    gpa_to_gfn(gpa) >= range->start &&
+		    gpa_to_gfn(gpa) < range->end)
+			kvm_make_request_and_kick(KVM_REQ_VMSA_PAGE_RELOAD, vcpu);
+	}
+}
+
 int sev_gmem_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn, bool is_private)
 {
 	int level, rc;
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 3d2b4e67967f..9d3630837a7d 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -5463,9 +5463,15 @@ struct kvm_x86_ops svm_x86_ops __initdata = {
 	.mem_enc_register_region = sev_mem_enc_register_region,
 	.mem_enc_unregister_region = sev_mem_enc_unregister_region,
 	.guest_memory_reclaimed = sev_guest_memory_reclaimed,
+	.reload_vmsa = sev_snp_reload_vmsa,
 
 	.vm_copy_enc_context_from = sev_vm_copy_enc_context_from,
 	.vm_move_enc_context_from = sev_vm_move_enc_context_from,
+
+	.gmem_make_private = sev_gmem_make_private,
+	.gmem_make_shared = sev_gmem_make_shared,
+	.gmem_invalidate_range = sev_gmem_invalidate_range,
+	.gmem_max_mapping_level = sev_gmem_max_mapping_level,
 #endif
 	.check_emulate_instruction = svm_check_emulate_instruction,
 
@@ -5477,10 +5483,6 @@ struct kvm_x86_ops svm_x86_ops __initdata = {
 	.vcpu_deliver_sipi_vector = svm_vcpu_deliver_sipi_vector,
 	.vcpu_get_apicv_inhibit_reasons = avic_vcpu_get_apicv_inhibit_reasons,
 	.alloc_apic_backing_page = svm_alloc_apic_backing_page,
-
-	.gmem_prepare = sev_gmem_prepare,
-	.gmem_invalidate = sev_gmem_invalidate,
-	.gmem_max_mapping_level = sev_gmem_max_mapping_level,
 };
 
 /*
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index d63e5878988a..16fdd6826c2c 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -272,7 +272,8 @@ struct vcpu_sev_es_state {
 	u64 ghcb_registered_gpa;
 
 	struct mutex snp_vmsa_mutex; /* Used to handle concurrent updates of VMSA. */
-	gpa_t snp_vmsa_gpa;
+	gpa_t snp_pending_vmsa_gpa;
+	gpa_t snp_guest_vmsa_gpa;
 	bool snp_ap_waiting_for_reset;
 	bool snp_has_guest_vmsa;
 };
@@ -996,6 +997,7 @@ static inline struct page *snp_safe_alloc_page(void)
 {
 	return snp_safe_alloc_page_node(numa_node_id(), GFP_KERNEL_ACCOUNT);
 }
+void sev_snp_reload_vmsa(struct kvm_vcpu *vcpu);
 
 int sev_vcpu_create(struct kvm_vcpu *vcpu);
 void sev_free_vcpu(struct kvm_vcpu *vcpu);
@@ -1008,8 +1010,9 @@ int sev_cpu_init(struct svm_cpu_data *sd);
 int sev_dev_get_attr(u32 group, u64 attr, u64 *val);
 extern unsigned int max_sev_asid;
 void sev_handle_rmp_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code);
-int sev_gmem_prepare(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order);
-void sev_gmem_invalidate(kvm_pfn_t start, kvm_pfn_t end);
+int sev_gmem_make_private(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, kvm_pfn_t nr_pages);
+void sev_gmem_make_shared(kvm_pfn_t pfn, kvm_pfn_t nr_pages);
+void sev_gmem_invalidate_range(struct kvm *kvm, struct kvm_gfn_range *range);
 int sev_gmem_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn, bool is_private);
 struct vmcb_save_area *sev_decrypt_vmsa(struct kvm_vcpu *vcpu);
 void sev_free_decrypted_vmsa(struct kvm_vcpu *vcpu, struct vmcb_save_area *vmsa);
@@ -1035,16 +1038,6 @@ static inline int sev_cpu_init(struct svm_cpu_data *sd) { return 0; }
 static inline int sev_dev_get_attr(u32 group, u64 attr, u64 *val) { return -ENXIO; }
 #define max_sev_asid 0
 static inline void sev_handle_rmp_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code) {}
-static inline int sev_gmem_prepare(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order)
-{
-	return 0;
-}
-static inline void sev_gmem_invalidate(kvm_pfn_t start, kvm_pfn_t end) {}
-static inline int sev_gmem_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn, bool is_private)
-{
-	return 0;
-}
-
 static inline struct vmcb_save_area *sev_decrypt_vmsa(struct kvm_vcpu *vcpu)
 {
 	return NULL;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2b8474812303..9134f774ea3d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3939,7 +3939,10 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
 			break;
 		fallthrough;
 	case KVM_CAP_DISABLE_QUIRKS:
-		kvm->arch.disabled_quirks |= cap->args[0] & kvm_caps.supported_quirks;
+		mutex_lock(&kvm->lock);
+		WRITE_ONCE(kvm->arch.disabled_quirks,
+			   kvm->arch.disabled_quirks | (cap->args[0] & kvm_caps.supported_quirks));
+		mutex_unlock(&kvm->lock);
 		r = 0;
 		break;
 	case KVM_CAP_SPLIT_IRQCHIP: {
@@ -8167,6 +8170,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 				goto out;
 			}
 		}
+		if (kvm_check_request(KVM_REQ_VMSA_PAGE_RELOAD, vcpu))
+			kvm_x86_call(reload_vmsa)(vcpu);
 	}
 
 	if (kvm_check_request(KVM_REQ_EVENT, vcpu) || req_int_win ||
@@ -10590,17 +10595,25 @@ bool kvm_arch_supports_gmem_init_shared(struct kvm *kvm)
 	return !kvm_arch_has_private_mem(kvm);
 }
 
-#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_PREPARE
-int kvm_arch_gmem_prepare(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, int max_order)
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT
+int kvm_arch_gmem_make_private(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn,
+			       kvm_pfn_t nr_pages)
 {
-	return kvm_x86_call(gmem_prepare)(kvm, pfn, gfn, max_order);
+	return kvm_x86_call(gmem_make_private)(kvm, gfn, pfn, nr_pages);
+}
+#endif
+
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_RECLAIM
+void kvm_arch_gmem_reclaim(kvm_pfn_t pfn, kvm_pfn_t nr_pages)
+{
+	kvm_x86_call(gmem_make_shared)(pfn, nr_pages);
 }
 #endif
 
 #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
-void kvm_arch_gmem_invalidate(kvm_pfn_t start, kvm_pfn_t end)
+void kvm_arch_gmem_invalidate_range(struct kvm *kvm, struct kvm_gfn_range *range)
 {
-	kvm_x86_call(gmem_invalidate)(start, end);
+	kvm_x86_call(gmem_invalidate_range)(kvm, range);
 }
 #endif
 #endif
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 8ece468087a8..75f13d88db58 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -304,7 +304,7 @@ static inline bool vcpu_match_mmio_gpa(struct kvm_vcpu *vcpu, gpa_t gpa)
 
 static inline bool kvm_check_has_quirk(struct kvm *kvm, u64 quirk)
 {
-	return !(kvm->arch.disabled_quirks & quirk);
+	return !(READ_ONCE(kvm->arch.disabled_quirks) & quirk);
 }
 
 static __always_inline void kvm_request_l1tf_flush_l1d(void)
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 6f883ed82581..7f8946571b42 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -2573,8 +2573,9 @@ static inline int kvm_gmem_get_pfn(struct kvm *kvm,
 }
 #endif /* CONFIG_KVM_GUEST_MEMFD */
 
-#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_PREPARE
-int kvm_arch_gmem_prepare(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, int max_order);
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT
+int kvm_arch_gmem_make_private(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn,
+			       kvm_pfn_t nr_pages);
 #endif
 
 #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_POPULATE
@@ -2607,8 +2608,12 @@ long kvm_gmem_populate(struct kvm *kvm, gfn_t start_gfn, void __user *src,
 		       kvm_gmem_populate_cb post_populate, void *opaque);
 #endif
 
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_RECLAIM
+void kvm_arch_gmem_reclaim(kvm_pfn_t pfn, kvm_pfn_t nr_pages);
+#endif
+
 #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
-void kvm_arch_gmem_invalidate(kvm_pfn_t start, kvm_pfn_t end);
+void kvm_arch_gmem_invalidate_range(struct kvm *kvm, struct kvm_gfn_range *range);
 #endif
 
 #ifdef CONFIG_KVM_GENERIC_PRE_FAULT_MEMORY
diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
index 794976b88c6f..c3c0ee253fc7 100644
--- a/virt/kvm/Kconfig
+++ b/virt/kvm/Kconfig
@@ -107,7 +107,11 @@ config KVM_GUEST_MEMFD
        select XARRAY_MULTI
        bool
 
-config HAVE_KVM_ARCH_GMEM_PREPARE
+config HAVE_KVM_ARCH_GMEM_CONVERT
+       bool
+       depends on KVM_GUEST_MEMFD
+
+config HAVE_KVM_ARCH_GMEM_RECLAIM
        bool
        depends on KVM_GUEST_MEMFD
 
diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c
index 8e3bdda28ece..b596486d184c 100644
--- a/virt/kvm/guest_memfd.c
+++ b/virt/kvm/guest_memfd.c
@@ -61,52 +61,14 @@ static pgoff_t kvm_gmem_get_index(struct kvm_memory_slot *slot, gfn_t gfn)
 	return gfn - slot->base_gfn + slot->gmem.pgoff;
 }
 
-static int __kvm_gmem_prepare_folio(struct kvm *kvm, struct kvm_memory_slot *slot,
-				    pgoff_t index, struct folio *folio)
+static bool kvm_gmem_is_private_mem(struct inode *inode, pgoff_t index)
 {
-#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_PREPARE
-	kvm_pfn_t pfn = folio_file_pfn(folio, index);
-	gfn_t gfn = slot->base_gfn + index - slot->gmem.pgoff;
-	int rc = kvm_arch_gmem_prepare(kvm, gfn, pfn, folio_order(folio));
-	if (rc) {
-		pr_warn_ratelimited("gmem: Failed to prepare folio for index %lx GFN %llx PFN %llx error %d.\n",
-				    index, gfn, pfn, rc);
-		return rc;
-	}
-#endif
-
-	return 0;
+	return !(GMEM_I(inode)->flags & GUEST_MEMFD_FLAG_INIT_SHARED);
 }
 
-/*
- * Process @folio, which contains @gfn, so that the guest can use it.
- * The folio must be locked and the gfn must be contained in @slot.
- * On successful return the guest sees a zero page so as to avoid
- * leaking host data and the up-to-date flag is set.
- */
-static int kvm_gmem_prepare_folio(struct kvm *kvm, struct kvm_memory_slot *slot,
-				  gfn_t gfn, struct folio *folio)
+static bool kvm_gmem_is_shared_mem(struct inode *inode, pgoff_t index)
 {
-	pgoff_t index;
-
-	/*
-	 * Preparing huge folios should always be safe, since it should
-	 * be possible to split them later if needed.
-	 *
-	 * Right now the folio order is always going to be zero, but the
-	 * code is ready for huge folios.  The only assumption is that
-	 * the base pgoff of memslots is naturally aligned with the
-	 * requested page order, ensuring that huge folios can also use
-	 * huge page table entries for GPA->HPA mapping.
-	 *
-	 * The order will be passed when creating the guest_memfd, and
-	 * checked when creating memslots.
-	 */
-	WARN_ON(!IS_ALIGNED(slot->gmem.pgoff, folio_nr_pages(folio)));
-	index = kvm_gmem_get_index(slot, gfn);
-	index = ALIGN_DOWN(index, folio_nr_pages(folio));
-
-	return __kvm_gmem_prepare_folio(kvm, slot, index, folio);
+	return !kvm_gmem_is_private_mem(inode, index);
 }
 
 /*
@@ -186,6 +148,10 @@ static void __kvm_gmem_invalidate_start(struct gmem_file *f, pgoff_t start,
 		}
 
 		flush |= kvm_mmu_unmap_gfn_range(kvm, &gfn_range);
+
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
+		kvm_arch_gmem_invalidate_range(kvm, &gfn_range);
+#endif
 	}
 
 	if (flush)
@@ -398,7 +364,7 @@ static vm_fault_t kvm_gmem_fault_user_mapping(struct vm_fault *vmf)
 	if (((loff_t)vmf->pgoff << PAGE_SHIFT) >= i_size_read(inode))
 		return VM_FAULT_SIGBUS;
 
-	if (!(GMEM_I(inode)->flags & GUEST_MEMFD_FLAG_INIT_SHARED))
+	if (!kvm_gmem_is_shared_mem(inode, vmf->pgoff))
 		return VM_FAULT_SIGBUS;
 
 	folio = kvm_gmem_get_folio(inode, vmf->pgoff);
@@ -524,14 +490,10 @@ static int kvm_gmem_error_folio(struct address_space *mapping, struct folio *fol
 	return MF_DELAYED;
 }
 
-#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_RECLAIM
 static void kvm_gmem_free_folio(struct folio *folio)
 {
-	struct page *page = folio_page(folio, 0);
-	kvm_pfn_t pfn = page_to_pfn(page);
-	int order = folio_order(folio);
-
-	kvm_arch_gmem_invalidate(pfn, pfn + (1ul << order));
+	kvm_arch_gmem_reclaim(folio_file_pfn(folio, 0), folio_nr_pages(folio));
 }
 #endif
 
@@ -539,7 +501,7 @@ static const struct address_space_operations kvm_gmem_aops = {
 	.dirty_folio = noop_dirty_folio,
 	.migrate_folio	= kvm_gmem_migrate_folio,
 	.error_remove_folio = kvm_gmem_error_folio,
-#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_RECLAIM
 	.free_folio = kvm_gmem_free_folio,
 #endif
 };
@@ -794,7 +756,9 @@ int kvm_gmem_get_pfn(struct kvm *kvm, struct kvm_memory_slot *slot,
 {
 	pgoff_t index = kvm_gmem_get_index(slot, gfn);
 	struct folio *folio;
-	int r = 0;
+	int r = 0, __order;
+
+	max_order = max_order ?: &__order;
 
 	CLASS(gmem_get_file, file)(slot);
 	if (!file)
@@ -809,7 +773,11 @@ int kvm_gmem_get_pfn(struct kvm *kvm, struct kvm_memory_slot *slot,
 		folio_mark_uptodate(folio);
 	}
 
-	r = kvm_gmem_prepare_folio(kvm, slot, gfn, folio);
+#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT
+	if (kvm_gmem_is_private_mem(file_inode(file), index))
+		r = kvm_arch_gmem_make_private(kvm, gfn, *pfn,
+					       (kvm_pfn_t)1 << *max_order);
+#endif
 
 	folio_unlock(folio);