diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 326cdfec74a1..5d474360bf6c 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1486,8 +1486,9 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
 }
 
 int kvm_arch_prepare_memory_region(struct kvm *kvm,
-				   struct kvm_memory_slot *memslot,
 				   const struct kvm_userspace_memory_region *mem,
+				   const struct kvm_memory_slot *old,
+				   struct kvm_memory_slot *new,
 				   enum kvm_mr_change change)
 {
 	hva_t hva = mem->userspace_addr;
@@ -1502,7 +1503,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
 	 * Prevent userspace from creating a memory region outside of the IPA
 	 * space addressable by the KVM guest IPA space.
 	 */
-	if ((memslot->base_gfn + memslot->npages) > (kvm_phys_size(kvm) >> PAGE_SHIFT))
+	if ((new->base_gfn + new->npages) > (kvm_phys_size(kvm) >> PAGE_SHIFT))
 		return -EFAULT;
 
 	mmap_read_lock(current->mm);
@@ -1536,7 +1537,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
 
 		if (vma->vm_flags & VM_PFNMAP) {
 			/* IO region dirty page logging not allowed */
-			if (memslot->flags & KVM_MEM_LOG_DIRTY_PAGES) {
+			if (new->flags & KVM_MEM_LOG_DIRTY_PAGES) {
 				ret = -EINVAL;
 				break;
 			}
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 043204cd585f..b2ce10784eb0 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -214,8 +214,9 @@ void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
 }
 
 int kvm_arch_prepare_memory_region(struct kvm *kvm,
-				   struct kvm_memory_slot *memslot,
 				   const struct kvm_userspace_memory_region *mem,
+				   const struct kvm_memory_slot *old,
+				   struct kvm_memory_slot *new,
 				   enum kvm_mr_change change)
 {
 	return 0;
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 671fbd1a765e..b01760dd1374 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -200,12 +200,13 @@ extern void kvmppc_core_destroy_vm(struct kvm *kvm);
 extern void kvmppc_core_free_memslot(struct kvm *kvm,
 				     struct kvm_memory_slot *slot);
 extern int kvmppc_core_prepare_memory_region(struct kvm *kvm,
-				struct kvm_memory_slot *memslot,
 				const struct kvm_userspace_memory_region *mem,
+				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *new,
 				enum kvm_mr_change change);
 extern void kvmppc_core_commit_memory_region(struct kvm *kvm,
 				const struct kvm_userspace_memory_region *mem,
-				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *old,
 				const struct kvm_memory_slot *new,
 				enum kvm_mr_change change);
 extern int kvm_vm_ioctl_get_smmu_info(struct kvm *kvm,
@@ -274,12 +275,13 @@ struct kvmppc_ops {
 	int (*get_dirty_log)(struct kvm *kvm, struct kvm_dirty_log *log);
 	void (*flush_memslot)(struct kvm *kvm, struct kvm_memory_slot *memslot);
 	int (*prepare_memory_region)(struct kvm *kvm,
-				     struct kvm_memory_slot *memslot,
 				     const struct kvm_userspace_memory_region *mem,
+				     const struct kvm_memory_slot *old,
+				     struct kvm_memory_slot *new,
 				     enum kvm_mr_change change);
 	void (*commit_memory_region)(struct kvm *kvm,
 				     const struct kvm_userspace_memory_region *mem,
-				     const struct kvm_memory_slot *old,
+				     struct kvm_memory_slot *old,
 				     const struct kvm_memory_slot *new,
 				     enum kvm_mr_change change);
 	bool (*unmap_gfn_range)(struct kvm *kvm, struct kvm_gfn_range *range);
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index b785f6772391..8250e8308674 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -847,17 +847,17 @@ void kvmppc_core_flush_memslot(struct kvm *kvm, struct kvm_memory_slot *memslot)
 }
 
 int kvmppc_core_prepare_memory_region(struct kvm *kvm,
-				struct kvm_memory_slot *memslot,
-				const struct kvm_userspace_memory_region *mem,
-				enum kvm_mr_change change)
+				      const struct kvm_userspace_memory_region *mem,
+				      const struct kvm_memory_slot *old,
+				      struct kvm_memory_slot *new,
+				      enum kvm_mr_change change)
 {
-	return kvm->arch.kvm_ops->prepare_memory_region(kvm, memslot, mem,
-							change);
+	return kvm->arch.kvm_ops->prepare_memory_region(kvm, mem, old, new, change);
 }
 
 void kvmppc_core_commit_memory_region(struct kvm *kvm,
 				const struct kvm_userspace_memory_region *mem,
-				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *old,
 				const struct kvm_memory_slot *new,
 				enum kvm_mr_change change)
 {
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 32873c6985f9..d7594d49d288 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4854,17 +4854,20 @@ static void kvmppc_core_free_memslot_hv(struct kvm_memory_slot *slot)
 }
 
 static int kvmppc_core_prepare_memory_region_hv(struct kvm *kvm,
-					struct kvm_memory_slot *slot,
-					const struct kvm_userspace_memory_region *mem,
-					enum kvm_mr_change change)
+				const struct kvm_userspace_memory_region *mem,
+				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *new,
+				enum kvm_mr_change change)
 {
 	unsigned long npages = mem->memory_size >> PAGE_SHIFT;
 
 	if (change == KVM_MR_CREATE) {
-		slot->arch.rmap = vzalloc(array_size(npages,
-					  sizeof(*slot->arch.rmap)));
-		if (!slot->arch.rmap)
+		new->arch.rmap = vzalloc(array_size(npages,
+					  sizeof(*new->arch.rmap)));
+		if (!new->arch.rmap)
 			return -ENOMEM;
+	} else if (change != KVM_MR_DELETE) {
+		new->arch.rmap = old->arch.rmap;
 	}
 
 	return 0;
@@ -4872,7 +4875,7 @@ static int kvmppc_core_prepare_memory_region_hv(struct kvm *kvm,
 
 static void kvmppc_core_commit_memory_region_hv(struct kvm *kvm,
 				const struct kvm_userspace_memory_region *mem,
-				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *old,
 				const struct kvm_memory_slot *new,
 				enum kvm_mr_change change)
 {
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index f981f2c1b7e9..6a94831487ae 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -1899,16 +1899,17 @@ static void kvmppc_core_flush_memslot_pr(struct kvm *kvm,
 }
 
 static int kvmppc_core_prepare_memory_region_pr(struct kvm *kvm,
-					struct kvm_memory_slot *memslot,
-					const struct kvm_userspace_memory_region *mem,
-					enum kvm_mr_change change)
+				const struct kvm_userspace_memory_region *mem,
+				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *new,
+				enum kvm_mr_change change)
 {
 	return 0;
 }
 
 static void kvmppc_core_commit_memory_region_pr(struct kvm *kvm,
 				const struct kvm_userspace_memory_region *mem,
-				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *old,
 				const struct kvm_memory_slot *new,
 				enum kvm_mr_change change)
 {
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 42e418153324..47f691387171 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1821,8 +1821,9 @@ void kvmppc_core_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
 }
 
 int kvmppc_core_prepare_memory_region(struct kvm *kvm,
-				      struct kvm_memory_slot *memslot,
 				      const struct kvm_userspace_memory_region *mem,
+				      const struct kvm_memory_slot *old,
+				      struct kvm_memory_slot *new,
 				      enum kvm_mr_change change)
 {
 	return 0;
@@ -1830,7 +1831,7 @@ int kvmppc_core_prepare_memory_region(struct kvm *kvm,
 
 void kvmppc_core_commit_memory_region(struct kvm *kvm,
 				const struct kvm_userspace_memory_region *mem,
-				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *old,
 				const struct kvm_memory_slot *new,
 				enum kvm_mr_change change)
 {
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 166a55dc744a..cf0422c41359 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -698,11 +698,12 @@ void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
 }
 
 int kvm_arch_prepare_memory_region(struct kvm *kvm,
-				   struct kvm_memory_slot *memslot,
 				   const struct kvm_userspace_memory_region *mem,
+				   const struct kvm_memory_slot *old,
+				   struct kvm_memory_slot *new,
 				   enum kvm_mr_change change)
 {
-	return kvmppc_core_prepare_memory_region(kvm, memslot, mem, change);
+	return kvmppc_core_prepare_memory_region(kvm, mem, old, new, change);
 }
 
 void kvm_arch_commit_memory_region(struct kvm *kvm,
diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
index fc058ff5f4b6..50380f525345 100644
--- a/arch/riscv/kvm/mmu.c
+++ b/arch/riscv/kvm/mmu.c
@@ -477,8 +477,9 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
 }
 
 int kvm_arch_prepare_memory_region(struct kvm *kvm,
-				struct kvm_memory_slot *memslot,
 				const struct kvm_userspace_memory_region *mem,
+				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *new,
 				enum kvm_mr_change change)
 {
 	hva_t hva = mem->userspace_addr;
@@ -494,7 +495,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
 	 * Prevent userspace from creating a memory region outside of the GPA
 	 * space addressable by the KVM guest GPA space.
 	 */
-	if ((memslot->base_gfn + memslot->npages) >=
+	if ((new->base_gfn + new->npages) >=
 	    (stage2_gpa_size >> PAGE_SHIFT))
 		return -EFAULT;
 
@@ -541,7 +542,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
 			pa += vm_start - vma->vm_start;
 
 			/* IO region dirty page logging not allowed */
-			if (memslot->flags & KVM_MEM_LOG_DIRTY_PAGES) {
+			if (new->flags & KVM_MEM_LOG_DIRTY_PAGES) {
 				ret = -EINVAL;
 				goto out;
 			}
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 33bc0a1cb328..3d943c78a770 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -5007,8 +5007,9 @@ vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
 
 /* Section: memory related */
 int kvm_arch_prepare_memory_region(struct kvm *kvm,
-				   struct kvm_memory_slot *memslot,
 				   const struct kvm_userspace_memory_region *mem,
+				   const struct kvm_memory_slot *old,
+				   struct kvm_memory_slot *new,
 				   enum kvm_mr_change change)
 {
 	/* A few sanity checks. We can have memory slots which have to be
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a05a26471f19..d6362406a82e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -11723,13 +11723,20 @@ void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen)
 }
 
 int kvm_arch_prepare_memory_region(struct kvm *kvm,
-				struct kvm_memory_slot *memslot,
-				const struct kvm_userspace_memory_region *mem,
-				enum kvm_mr_change change)
+				   const struct kvm_userspace_memory_region *mem,
+				   const struct kvm_memory_slot *old,
+				   struct kvm_memory_slot *new,
+				   enum kvm_mr_change change)
 {
 	if (change == KVM_MR_CREATE || change == KVM_MR_MOVE)
-		return kvm_alloc_memslot_metadata(kvm, memslot,
+		return kvm_alloc_memslot_metadata(kvm, new,
 						  mem->memory_size >> PAGE_SHIFT);
+
+	if (change == KVM_MR_FLAGS_ONLY)
+		memcpy(&new->arch, &old->arch, sizeof(old->arch));
+	else if (WARN_ON_ONCE(change != KVM_MR_DELETE))
+		return -EIO;
+
 	return 0;
 }
 
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index a6830966f8eb..1024b40b1567 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -835,8 +835,9 @@ int __kvm_set_memory_region(struct kvm *kvm,
 void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot);
 void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen);
 int kvm_arch_prepare_memory_region(struct kvm *kvm,
-				struct kvm_memory_slot *memslot,
 				const struct kvm_userspace_memory_region *mem,
+				const struct kvm_memory_slot *old,
+				struct kvm_memory_slot *new,
 				enum kvm_mr_change change);
 void kvm_arch_commit_memory_region(struct kvm *kvm,
 				const struct kvm_userspace_memory_region *mem,
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 683a5ef6f71e..67b081d477d8 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1638,10 +1638,7 @@ static int kvm_set_memslot(struct kvm *kvm,
 		old.as_id = new->as_id;
 	}
 
-	/* Copy the arch-specific data, again after (re)acquiring slots_arch_lock. */
-	memcpy(&new->arch, &old.arch, sizeof(old.arch));
-
-	r = kvm_arch_prepare_memory_region(kvm, new, mem, change);
+	r = kvm_arch_prepare_memory_region(kvm, mem, &old, new, change);
 	if (r)
 		goto out_slots;
 
