diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index d03842abae57..795773f5db63 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -192,11 +192,24 @@ struct kvm_xen_exit {
 /* Flags that describe what fields in emulation_failure hold valid data. */
 #define KVM_INTERNAL_ERROR_EMULATION_FLAG_INSTRUCTION_BYTES (1ULL << 0)
 
+/*
+ * struct kvm_run can be modified by userspace at any time, so KVM must be
+ * careful to avoid TOCTOU bugs. In order to protect KVM, HINT_UNSAFE_IN_KVM()
+ * renames fields in struct kvm_run from <symbol> to <symbol>__unsafe when
+ * compiled into the kernel, ensuring that any use within KVM is obvious and
+ * gets extra scrutiny.
+ */
+#ifdef __KERNEL__
+#define HINT_UNSAFE_IN_KVM(_symbol) _symbol##__unsafe
+#else
+#define HINT_UNSAFE_IN_KVM(_symbol) _symbol
+#endif
+
 /* for KVM_RUN, returned by mmap(vcpu_fd, offset=0) */
 struct kvm_run {
 	/* in */
 	__u8 request_interrupt_window;
-	__u8 immediate_exit;
+	__u8 HINT_UNSAFE_IN_KVM(immediate_exit);
 	__u8 padding1[6];
 
 	/* out */
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 66bfdfa11805..2fed9a9b8bd6 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -4435,7 +4435,7 @@ static long kvm_vcpu_ioctl(struct file *filp,
 				synchronize_rcu();
 			put_pid(oldpid);
 		}
-		vcpu->wants_to_run = !READ_ONCE(vcpu->run->immediate_exit);
+		vcpu->wants_to_run = !READ_ONCE(vcpu->run->immediate_exit__unsafe);
 		r = kvm_arch_vcpu_ioctl_run(vcpu);
 		vcpu->wants_to_run = false;