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diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S
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+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/linkage.h>
+#include <asm/asm.h>
+
+ .text
+
+/**
+ * vmx_vmenter - VM-Enter the current loaded VMCS
+ *
+ * %RFLAGS.ZF: !VMCS.LAUNCHED, i.e. controls VMLAUNCH vs. VMRESUME
+ *
+ * Returns:
+ * %RFLAGS.CF is set on VM-Fail Invalid
+ * %RFLAGS.ZF is set on VM-Fail Valid
+ * %RFLAGS.{CF,ZF} are cleared on VM-Success, i.e. VM-Exit
+ *
+ * Note that VMRESUME/VMLAUNCH fall-through and return directly if
+ * they VM-Fail, whereas a successful VM-Enter + VM-Exit will jump
+ * to vmx_vmexit.
+ */
+ENTRY(vmx_vmenter)
+ /* EFLAGS.ZF is set if VMCS.LAUNCHED == 0 */
+ je 2f
+
+1: vmresume
+ ret
+
+2: vmlaunch
+ ret
+
+3: cmpb $0, kvm_rebooting
+ jne 4f
+ call kvm_spurious_fault
+4: ret
+
+ .pushsection .fixup, "ax"
+5: jmp 3b
+ .popsection
+
+ _ASM_EXTABLE(1b, 5b)
+ _ASM_EXTABLE(2b, 5b)
+
+ENDPROC(vmx_vmenter)
+
+/**
+ * vmx_vmexit - Handle a VMX VM-Exit
+ *
+ * Returns:
+ * %RFLAGS.{CF,ZF} are cleared on VM-Success, i.e. VM-Exit
+ *
+ * This is vmx_vmenter's partner in crime. On a VM-Exit, control will jump
+ * here after hardware loads the host's state, i.e. this is the destination
+ * referred to by VMCS.HOST_RIP.
+ */
+ENTRY(vmx_vmexit)
+ ret
+ENDPROC(vmx_vmexit)