[PATCH 11/11] nEPT: Provide the correct exit qualification upon EPT

[Jun Nakajima <jun.nakajima@intel.com>]

Save [2:0] of exit qualificaiton at EPT violation, and use the information when injecting EPT violation.

Signed-off-by: Jun Nakajima <jun.nakajima@intel.com>
Signed-off-by: Xinhao Xu <xinhao.xu@intel.com>
---
 arch/x86/include/asm/kvm_host.h | 2 ++
 arch/x86/kvm/paging_tmpl.h      | 5 +++++
 arch/x86/kvm/vmx.c              | 3 +++
 3 files changed, 10 insertions(+)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 4979778..e029bba 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -504,6 +504,8 @@ struct kvm_vcpu_arch {
 	 * instruction.
 	 */
 	bool write_fault_to_shadow_pgtable;
+
+	unsigned long exit_qualification; /* set at EPT violation at this point */
 };
 
 struct kvm_lpage_info {
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index e13b6c5..bd370e7 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -349,7 +349,12 @@ error:
 
 	walker->fault.vector = PF_VECTOR;
 	walker->fault.error_code_valid = true;
+#if PTTYPE != PTTYPE_EPT
 	walker->fault.error_code = errcode;
+#else
+	/* Reuse bits [2:0] of EPT violation */
+	walker->fault.error_code = vcpu->arch.exit_qualification & 0x7;
+#endif
 	walker->fault.address = addr;
 	walker->fault.nested_page_fault = mmu != vcpu->arch.walk_mmu;
 
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 95304cc..61e2853 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -425,6 +425,7 @@ struct vcpu_vmx {
 	ktime_t entry_time;
 	s64 vnmi_blocked_time;
 	u32 exit_reason;
+	unsigned long exit_qualification;
 
 	bool rdtscp_enabled;
 
@@ -5074,6 +5075,8 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu)
 	/* ept page table is present? */
 	error_code |= (exit_qualification >> 3) & 0x1;
 
+    vcpu->arch.exit_qualification = exit_qualification;
+
 	return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
 }
 
-- 
1.8.2.1.610.g562af5b