linux-kernel - [RFC PATCH 04/13] kvm, vmx: Add support for gva exit qualification

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Date:   Thu,  3 Oct 2019 14:23:51 -0700
From:   Rick Edgecombe <rick.p.edgecombe@...el.com>
To:     kvm@...r.kernel.org, linux-kernel@...r.kernel.org, x86@...nel.org,
        linux-mm@...ck.org, luto@...nel.org, peterz@...radead.org,
        dave.hansen@...el.com, pbonzini@...hat.com,
        sean.j.christopherson@...el.com, keescook@...omium.org
Cc:     kristen@...ux.intel.com, deneen.t.dock@...el.com,
        Rick Edgecombe <rick.p.edgecombe@...el.com>
Subject: [RFC PATCH 04/13] kvm, vmx: Add support for gva exit qualification

VMX supports providing the guest virtual address that caused and EPT
violation. Add support for this so it can be used by the KVM XO feature.

Signed-off-by: Rick Edgecombe <rick.p.edgecombe@...el.com>
---
 arch/x86/include/asm/kvm_host.h | 4 ++++
 arch/x86/include/asm/vmx.h      | 1 +
 arch/x86/kvm/vmx/vmx.c          | 5 +++++
 arch/x86/kvm/x86.c              | 1 +
 4 files changed, 11 insertions(+)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index bdc16b0aa7c6..b363a7fc47b0 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -781,6 +781,10 @@ struct kvm_vcpu_arch {
 	bool gpa_available;
 	gpa_t gpa_val;
 
+	/* GVA available */
+	bool gva_available;
+	gva_t gva_val;
+
 	/* be preempted when it's in kernel-mode(cpl=0) */
 	bool preempted_in_kernel;
 
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index a39136b0d509..67457f2d19e2 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -522,6 +522,7 @@ struct vmx_msr_entry {
 #define EPT_VIOLATION_READABLE_BIT	3
 #define EPT_VIOLATION_WRITABLE_BIT	4
 #define EPT_VIOLATION_EXECUTABLE_BIT	5
+#define EPT_VIOLATION_GVA_LINEAR_VALID	7
 #define EPT_VIOLATION_GVA_TRANSLATED_BIT 8
 #define EPT_VIOLATION_ACC_READ		(1 << EPT_VIOLATION_ACC_READ_BIT)
 #define EPT_VIOLATION_ACC_WRITE		(1 << EPT_VIOLATION_ACC_WRITE_BIT)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index c030c96fc81a..a30dbab8a2d4 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5116,6 +5116,11 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu)
 	error_code |= (exit_qualification & 0x100) != 0 ?
 	       PFERR_GUEST_FINAL_MASK : PFERR_GUEST_PAGE_MASK;
 
+	if (exit_qualification | EPT_VIOLATION_GVA_LINEAR_VALID) {
+		vcpu->arch.gva_available = true;
+		vcpu->arch.gva_val = vmcs_readl(GUEST_LINEAR_ADDRESS);
+	}
+
 	vcpu->arch.exit_qualification = exit_qualification;
 	return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
 }
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 91602d310a3f..aa138d3a86c5 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8092,6 +8092,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 		kvm_lapic_sync_from_vapic(vcpu);
 
 	vcpu->arch.gpa_available = false;
+	vcpu->arch.gva_available = false;
 	r = kvm_x86_ops->handle_exit(vcpu);
 	return r;
 
-- 
2.17.1