diff mbox

[9/24] Implement VMCLEAR

Message ID 201006131227.o5DCRAB0012968@rice.haifa.ibm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Nadav Har'El June 13, 2010, 12:27 p.m. UTC
None
diff mbox

Patch

--- .before/arch/x86/kvm/vmx.c	2010-06-13 15:01:29.000000000 +0300
+++ .after/arch/x86/kvm/vmx.c	2010-06-13 15:01:29.000000000 +0300
@@ -138,6 +138,8 @@  struct __attribute__ ((__packed__)) vmcs
 	 */
 	u32 revision_id;
 	u32 abort;
+
+	bool launch_state; /* set to 0 by VMCLEAR, to 1 by VMLAUNCH */
 };
 
 struct vmcs_list {
@@ -3827,6 +3829,46 @@  static int read_guest_vmcs_gpa(struct kv
 	return 0;
 }
 
+static void clear_rflags_cf_zf(struct kvm_vcpu *vcpu)
+{
+	unsigned long rflags;
+	rflags = vmx_get_rflags(vcpu);
+	rflags &= ~(X86_EFLAGS_CF | X86_EFLAGS_ZF);
+	vmx_set_rflags(vcpu, rflags);
+}
+
+/* Emulate the VMCLEAR instruction */
+static int handle_vmclear(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+	gpa_t guest_vmcs_addr, save_current_vmptr;
+
+	if (!nested_vmx_check_permission(vcpu))
+		return 1;
+
+	if (read_guest_vmcs_gpa(vcpu, &guest_vmcs_addr))
+		return 1;
+
+	save_current_vmptr = vmx->nested.current_vmptr;
+
+	vmx->nested.current_vmptr = guest_vmcs_addr;
+	if (!nested_map_current(vcpu))
+		return 1;
+	vmx->nested.current_l2_page->launch_state = 0;
+	nested_unmap_current(vcpu);
+
+	nested_free_current_vmcs(vcpu);
+
+	if (save_current_vmptr == guest_vmcs_addr)
+		vmx->nested.current_vmptr = -1ull;
+	else
+		vmx->nested.current_vmptr = save_current_vmptr;
+
+	skip_emulated_instruction(vcpu);
+	clear_rflags_cf_zf(vcpu);
+	return 1;
+}
+
 static int handle_invlpg(struct kvm_vcpu *vcpu)
 {
 	unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
@@ -4109,7 +4151,7 @@  static int (*kvm_vmx_exit_handlers[])(st
 	[EXIT_REASON_HLT]                     = handle_halt,
 	[EXIT_REASON_INVLPG]		      = handle_invlpg,
 	[EXIT_REASON_VMCALL]                  = handle_vmcall,
-	[EXIT_REASON_VMCLEAR]	              = handle_vmx_insn,
+	[EXIT_REASON_VMCLEAR]	              = handle_vmclear,
 	[EXIT_REASON_VMLAUNCH]                = handle_vmx_insn,
 	[EXIT_REASON_VMPTRLD]                 = handle_vmx_insn,
 	[EXIT_REASON_VMPTRST]                 = handle_vmx_insn,