diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index c1f991c1ffa6..ca92b9e2cded 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -4697,6 +4697,45 @@ KVM_PV_VM_VERIFY
   Verify the integrity of the unpacked image. Only if this succeeds,
   KVM is allowed to start protected VCPUs.
 
+4.126 KVM_ADD_MSR_ALLOWLIST
+-------------------------
+
+:Capability: KVM_CAP_ADD_MSR_ALLOWLIST
+:Architectures: x86
+:Type: vm ioctl
+:Parameters: struct kvm_msr_allowlist
+:Returns: 0 on success, < 0 on error
+
+::
+
+  struct kvm_msr_allowlist {
+         __u32 flags;
+         __u32 nmsrs; /* number of msrs in bitmap */
+         __u32 base;  /* base address for the MSRs bitmap */
+         __u32 pad;
+
+         __u8 bitmap[0]; /* a set bit allows that the operation set in flags */
+  };
+
+This ioctl allows user space to define a set of bitmaps of MSR ranges to
+specify whether a certain MSR access is allowed or not.
+
+If this ioctl has never been invoked, MSR accesses are not guarded and the
+old KVM in-kernel emulation behavior is fully preserved.
+
+As soon as the first allow list was specified, only allowed MSR accesses
+are permitted inside of KVM's MSR code.
+
+Each allowlist specifies a range of MSRs to potentially allow access on.
+The range goes from MSR index [base .. base+nmsrs]. The flags field
+indicates whether reads, writes or both reads and writes are permitted
+by setting a 1 bit in the bitmap for the corresponding MSR index.
+
+If an MSR access is not permitted through the allow list, it generates a
+#GP inside the guest. When combined with KVM_CAP_X86_USER_SPACE_MSR, that
+allows user space to deflect and potentially handle various MSR accesses
+into user space.
+
 
 5. The kvm_run structure
 ========================
@@ -6213,3 +6252,17 @@ writes to user space. It can be enabled on a VM level. If enabled, MSR
 accesses that would usually trigger a #GP by KVM into the guest will
 instead get bounced to user space through the KVM_EXIT_RDMSR and
 KVM_EXIT_WRMSR exit notifications.
+
+8.25 KVM_CAP_ADD_MSR_ALLOWLIST
+------------------------------
+
+:Architectures: x86
+
+This capability indicates that KVM supports emulation of only select MSR
+registers. With this capability exposed, KVM exports a new VM ioctl
+KVM_ADD_MSR_ALLOWLIST which allows user space to specify bitmaps of MSR
+ranges that KVM should emulate in kernel space.
+
+In combination with KVM_CAP_X86_USER_SPACE_MSR, this allows user space to
+trap and emulate MSRs that are outside of the scope of KVM as well as
+limit the attack surface on KVM's MSR emulation code.
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 2f2307e71342..4b1ff7cb848f 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -901,6 +901,13 @@ struct kvm_hv {
 	struct kvm_hv_syndbg hv_syndbg;
 };
 
+struct msr_bitmap_range {
+	u32 flags;
+	u32 nmsrs;
+	u32 base;
+	unsigned long *bitmap;
+};
+
 enum kvm_irqchip_mode {
 	KVM_IRQCHIP_NONE,
 	KVM_IRQCHIP_KERNEL,       /* created with KVM_CREATE_IRQCHIP */
@@ -1005,6 +1012,9 @@ struct kvm_arch {
 	/* Deflect RDMSR and WRMSR to user space when they trigger a #GP */
 	bool user_space_msr_enabled;
 
+	struct msr_bitmap_range msr_allowlist_ranges[10];
+	int msr_allowlist_ranges_count;
+
 	struct kvm_pmu_event_filter *pmu_event_filter;
 	struct task_struct *nx_lpage_recovery_thread;
 };
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 0780f97c1850..bd640a43cad6 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -192,6 +192,21 @@ struct kvm_msr_list {
 	__u32 indices[0];
 };
 
+#define KVM_MSR_ALLOW_READ  (1 << 0)
+#define KVM_MSR_ALLOW_WRITE (1 << 1)
+
+/* Maximum size of the of the bitmap in bytes */
+#define KVM_MSR_ALLOWLIST_MAX_LEN 0x600
+
+/* for KVM_ADD_MSR_ALLOWLIST */
+struct kvm_msr_allowlist {
+	__u32 flags;
+	__u32 nmsrs; /* number of msrs in bitmap */
+	__u32 base;  /* base address for the MSRs bitmap */
+	__u32 pad;
+
+	__u8 bitmap[0]; /* a set bit allows that the operation set in flags */
+};
 
 struct kvm_cpuid_entry {
 	__u32 function;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 11e94a780656..924baec58d87 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1472,6 +1472,29 @@ void kvm_enable_efer_bits(u64 mask)
 }
 EXPORT_SYMBOL_GPL(kvm_enable_efer_bits);
 
+static bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type)
+{
+	struct msr_bitmap_range *ranges = vcpu->kvm->arch.msr_allowlist_ranges;
+	u32 count = vcpu->kvm->arch.msr_allowlist_ranges_count;
+	u32 i;
+
+	/* MSR allowlist not set up, allow everything */
+	if (!count)
+		return true;
+
+	for (i = 0; i < count; i++) {
+		u32 start = ranges[i].base;
+		u32 end = start + ranges[i].nmsrs;
+		int flags = ranges[i].flags;
+		unsigned long *bitmap = ranges[i].bitmap;
+
+		if ((index >= start) && (index < end) && (flags & type))
+			return !!test_bit(index - start, bitmap);
+	}
+
+	return false;
+}
+
 /*
  * Write @data into the MSR specified by @index.  Select MSR specific fault
  * checks are bypassed if @host_initiated is %true.
@@ -1483,6 +1506,9 @@ static int __kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data,
 {
 	struct msr_data msr;
 
+	if (!host_initiated && !kvm_msr_allowed(vcpu, index, KVM_MSR_ALLOW_WRITE))
+		return -ENOENT;
+
 	switch (index) {
 	case MSR_FS_BASE:
 	case MSR_GS_BASE:
@@ -1528,6 +1554,9 @@ int __kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data,
 	struct msr_data msr;
 	int ret;
 
+	if (!host_initiated && !kvm_msr_allowed(vcpu, index, KVM_MSR_ALLOW_READ))
+		return -ENOENT;
+
 	msr.index = index;
 	msr.host_initiated = host_initiated;
 
@@ -3549,6 +3578,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_EXCEPTION_PAYLOAD:
 	case KVM_CAP_SET_GUEST_DEBUG:
 	case KVM_CAP_X86_USER_SPACE_MSR:
+	case KVM_CAP_ADD_MSR_ALLOWLIST:
 		r = 1;
 		break;
 	case KVM_CAP_SYNC_REGS:
@@ -5074,6 +5104,92 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
 	return r;
 }
 
+static bool msr_range_overlaps(struct kvm *kvm, struct msr_bitmap_range *range)
+{
+	struct msr_bitmap_range *ranges = kvm->arch.msr_allowlist_ranges;
+	u32 i, count = kvm->arch.msr_allowlist_ranges_count;
+
+	for (i = 0; i < count; i++) {
+		u32 start = max(range->base, ranges[i].base);
+		u32 end = min(range->base + range->nmsrs,
+			      ranges[i].base + ranges[i].nmsrs);
+
+		if ((start < end) && (range->flags & ranges[i].flags))
+			return true;
+	}
+
+	return false;
+}
+
+static int kvm_vm_ioctl_add_msr_allowlist(struct kvm *kvm, void __user *argp)
+{
+	struct msr_bitmap_range *ranges = kvm->arch.msr_allowlist_ranges;
+	struct kvm_msr_allowlist __user *user_msr_allowlist = argp;
+	struct msr_bitmap_range range;
+	struct kvm_msr_allowlist kernel_msr_allowlist;
+	unsigned long *bitmap = NULL;
+	size_t bitmap_size;
+	int r;
+
+	if (copy_from_user(&kernel_msr_allowlist, user_msr_allowlist,
+			   sizeof(kernel_msr_allowlist))) {
+		r = -EFAULT;
+		goto out_err;
+	}
+
+	bitmap_size = BITS_TO_LONGS(kernel_msr_allowlist.nmsrs) * sizeof(long);
+	if (bitmap_size > KVM_MSR_ALLOWLIST_MAX_LEN) {
+		r = -EINVAL;
+		goto out_err;
+	}
+
+	bitmap = memdup_user(user_msr_allowlist->bitmap, bitmap_size);
+	if (IS_ERR(bitmap)) {
+		r = PTR_ERR(bitmap);
+		goto out_err;
+	}
+
+	range = (struct msr_bitmap_range) {
+		.flags = kernel_msr_allowlist.flags,
+		.base = kernel_msr_allowlist.base,
+		.nmsrs = kernel_msr_allowlist.nmsrs,
+		.bitmap = bitmap,
+	};
+
+	if (range.flags & ~(KVM_MSR_ALLOW_READ | KVM_MSR_ALLOW_WRITE)) {
+		r = -EINVAL;
+		goto out_err;
+	}
+
+	/*
+	 * Protect from concurrent calls to this function that could trigger
+	 * a TOCTOU violation on kvm->arch.msr_allowlist_ranges_count.
+	 */
+	mutex_lock(&kvm->lock);
+
+	if (kvm->arch.msr_allowlist_ranges_count >=
+	    ARRAY_SIZE(kvm->arch.msr_allowlist_ranges)) {
+		r = -E2BIG;
+		goto out_err;
+	}
+
+	if (msr_range_overlaps(kvm, &range)) {
+		r = -EINVAL;
+		goto out_err;
+	}
+
+	/* Everything ok, add this range identifier to our global pool */
+	ranges[kvm->arch.msr_allowlist_ranges_count++] = range;
+
+	mutex_unlock(&kvm->lock);
+
+	return 0;
+
+out_err:
+	kfree(bitmap);
+	return r;
+}
+
 long kvm_arch_vm_ioctl(struct file *filp,
 		       unsigned int ioctl, unsigned long arg)
 {
@@ -5380,6 +5496,9 @@ long kvm_arch_vm_ioctl(struct file *filp,
 	case KVM_SET_PMU_EVENT_FILTER:
 		r = kvm_vm_ioctl_set_pmu_event_filter(kvm, argp);
 		break;
+	case KVM_ADD_MSR_ALLOWLIST:
+		r = kvm_vm_ioctl_add_msr_allowlist(kvm, argp);
+		break;
 	default:
 		r = -ENOTTY;
 	}
@@ -10091,6 +10210,8 @@ void kvm_arch_pre_destroy_vm(struct kvm *kvm)
 
 void kvm_arch_destroy_vm(struct kvm *kvm)
 {
+	int i;
+
 	if (current->mm == kvm->mm) {
 		/*
 		 * Free memory regions allocated on behalf of userspace,
@@ -10107,6 +10228,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
 	}
 	if (kvm_x86_ops.vm_destroy)
 		kvm_x86_ops.vm_destroy(kvm);
+	for (i = 0; i < kvm->arch.msr_allowlist_ranges_count; i++)
+		kfree(kvm->arch.msr_allowlist_ranges[i].bitmap);
 	kvm_pic_destroy(kvm);
 	kvm_ioapic_destroy(kvm);
 	kvm_free_vcpus(kvm);
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index df237bf2bdc2..44ee9df8007f 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1042,6 +1042,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_HALT_POLL 182
 #define KVM_CAP_ASYNC_PF_INT 183
 #define KVM_CAP_X86_USER_SPACE_MSR 184
+#define KVM_CAP_ADD_MSR_ALLOWLIST 185
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
@@ -1543,6 +1544,9 @@ struct kvm_pv_cmd {
 /* Available with KVM_CAP_S390_PROTECTED */
 #define KVM_S390_PV_COMMAND		_IOWR(KVMIO, 0xc5, struct kvm_pv_cmd)
 
+/* Available with KVM_CAP_ADD_MSR_ALLOWLIST */
+#define KVM_ADD_MSR_ALLOWLIST     _IOW(KVMIO,  0xc6, struct kvm_msr_allowlist)
+
 /* Secure Encrypted Virtualization command */
 enum sev_cmd_id {
 	/* Guest initialization commands */
