KVM: VMX: Split out guts of EPT violation to common/exposed function

[ Upstream commit c8563d1 ]

The difference of TDX EPT violation is how to retrieve information, GPA,
and exit qualification.  To share the code to handle EPT violation, split
out the guts of EPT violation handler so that VMX/TDX exit handler can call
it after retrieving GPA and exit qualification.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Co-developed-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Message-ID: <20241112073528.22042-1-yan.y.zhao@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: d0164c1 ("KVM: VMX: Fix check for valid GVA on an EPT violation")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 6db2b0eb3251b45fab7310fd93f233bc22282933)
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>

Author: Sean Christopherson

arch/x86/kvm/vmx/common.h

@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __KVM_X86_VMX_COMMON_H
+#define __KVM_X86_VMX_COMMON_H
+
+#include <linux/kvm_host.h>
+
+#include "mmu.h"
+
+static inline int __vmx_handle_ept_violation(struct kvm_vcpu *vcpu, gpa_t gpa,
+					     unsigned long exit_qualification)
+{
+	u64 error_code;
+
+	/* Is it a read fault? */
+	error_code = (exit_qualification & EPT_VIOLATION_ACC_READ)
+		     ? PFERR_USER_MASK : 0;
+	/* Is it a write fault? */
+	error_code |= (exit_qualification & EPT_VIOLATION_ACC_WRITE)
+		      ? PFERR_WRITE_MASK : 0;
+	/* Is it a fetch fault? */
+	error_code |= (exit_qualification & EPT_VIOLATION_ACC_INSTR)
+		      ? PFERR_FETCH_MASK : 0;
+	/* ept page table entry is present? */
+	error_code |= (exit_qualification & EPT_VIOLATION_RWX_MASK)
+		      ? PFERR_PRESENT_MASK : 0;
+
+	if (error_code & EPT_VIOLATION_GVA_IS_VALID)
+		error_code |= (exit_qualification & EPT_VIOLATION_GVA_TRANSLATED) ?
+			      PFERR_GUEST_FINAL_MASK : PFERR_GUEST_PAGE_MASK;
+
+	return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
+}
+
+#endif /* __KVM_X86_VMX_COMMON_H */

arch/x86/kvm/vmx/vmx.c

@@ -53,6 +53,7 @@
 #include <trace/events/ipi.h>
 
 #include "capabilities.h"
+#include "common.h"
 #include "cpuid.h"
 #include "hyperv.h"
 #include "kvm_onhyperv.h"
@@ -5822,11 +5823,8 @@ static int handle_task_switch(struct kvm_vcpu *vcpu)
 
 static int handle_ept_violation(struct kvm_vcpu *vcpu)
 {
-	unsigned long exit_qualification;
+	unsigned long exit_qualification = vmx_get_exit_qual(vcpu);
 	gpa_t gpa;
-	u64 error_code;
-
-	exit_qualification = vmx_get_exit_qual(vcpu);
 
 	/*
 	 * EPT violation happened while executing iret from NMI,
@@ -5842,23 +5840,6 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu)
 	gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS);
 	trace_kvm_page_fault(vcpu, gpa, exit_qualification);
 
-	/* Is it a read fault? */
-	error_code = (exit_qualification & EPT_VIOLATION_ACC_READ)
-		     ? PFERR_USER_MASK : 0;
-	/* Is it a write fault? */
-	error_code |= (exit_qualification & EPT_VIOLATION_ACC_WRITE)
-		      ? PFERR_WRITE_MASK : 0;
-	/* Is it a fetch fault? */
-	error_code |= (exit_qualification & EPT_VIOLATION_ACC_INSTR)
-		      ? PFERR_FETCH_MASK : 0;
-	/* ept page table entry is present? */
-	error_code |= (exit_qualification & EPT_VIOLATION_RWX_MASK)
-		      ? PFERR_PRESENT_MASK : 0;
-
-	if (error_code & EPT_VIOLATION_GVA_IS_VALID)
-		error_code |= (exit_qualification & EPT_VIOLATION_GVA_TRANSLATED) ?
-			      PFERR_GUEST_FINAL_MASK : PFERR_GUEST_PAGE_MASK;
-
 	/*
 	 * Check that the GPA doesn't exceed physical memory limits, as that is
 	 * a guest page fault.  We have to emulate the instruction here, because
@@ -5870,7 +5851,7 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu)
 	if (unlikely(allow_smaller_maxphyaddr && !kvm_vcpu_is_legal_gpa(vcpu, gpa)))
 		return kvm_emulate_instruction(vcpu, 0);
 
-	return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
+	return __vmx_handle_ept_violation(vcpu, gpa, exit_qualification);
 }
 
 static int handle_ept_misconfig(struct kvm_vcpu *vcpu)