[PATCH 13/24] KVM: nVMX: pass advanced EPT violation vmexit info to guest

Paolo Bonzini posted 24 patches 1 week ago
[PATCH 13/24] KVM: nVMX: pass advanced EPT violation vmexit info to guest
Posted by Paolo Bonzini 1 week ago
KVM will use advanced vmexit information for EPT violations to
virtualize MBEC.  Pass it to the guest since it is easy and allows
testing nested nested.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/vmx.h     |  4 ++++
 arch/x86/kvm/mmu/paging_tmpl.h |  2 +-
 arch/x86/kvm/vmx/nested.c      | 13 +++++++++----
 3 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 2b449a3948d3..fcd623719334 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -524,6 +524,7 @@ enum vmcs_field {
 #define VMX_EPT_1GB_PAGE_BIT			(1ull << 17)
 #define VMX_EPT_INVEPT_BIT			(1ull << 20)
 #define VMX_EPT_AD_BIT				    (1ull << 21)
+#define VMX_EPT_ADVANCED_VMEXIT_INFO_BIT	(1ull << 22)
 #define VMX_EPT_EXTENT_CONTEXT_BIT		(1ull << 25)
 #define VMX_EPT_EXTENT_GLOBAL_BIT		(1ull << 26)
 
@@ -606,6 +607,9 @@ enum vm_entry_failure_code {
 					 EPT_VIOLATION_PROT_USER_EXEC)
 #define EPT_VIOLATION_GVA_IS_VALID	BIT(7)
 #define EPT_VIOLATION_GVA_TRANSLATED	BIT(8)
+#define EPT_VIOLATION_GVA_USER		BIT(9)
+#define EPT_VIOLATION_GVA_WRITABLE	BIT(10)
+#define EPT_VIOLATION_GVA_NX		BIT(11)
 
 #define EPT_VIOLATION_RWX_TO_PROT(__epte) (((__epte) & VMX_EPT_RWX_MASK) << 3)
 #define EPT_VIOLATION_USER_EXEC_TO_PROT(__epte) (((__epte) & VMX_EPT_USER_EXECUTABLE_MASK) >> 4)
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index fb1b5d8b23e5..09e2e630d4b6 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -491,7 +491,7 @@ static int FNAME(walk_addr_generic)(struct guest_walker *walker,
 	 * [2:0] - Derive from the access bits. The exit_qualification might be
 	 *         out of date if it is serving an EPT misconfiguration.
 	 * [5:3] - Calculated by the page walk of the guest EPT page tables
-	 * [7:8] - Derived from [7:8] of real exit_qualification
+	 * [7:11] - Derived from [7:11] of real exit_qualification
 	 *
 	 * The other bits are set to 0.
 	 */
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index adeb5a29169f..4b742a19bfde 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -443,10 +443,14 @@ static void nested_ept_inject_page_fault(struct kvm_vcpu *vcpu,
 			vm_exit_reason = EXIT_REASON_EPT_MISCONFIG;
 			exit_qualification = 0;
 		} else {
+			u64 mask = EPT_VIOLATION_GVA_IS_VALID |
+				EPT_VIOLATION_GVA_TRANSLATED;
+			if (vmx->nested.msrs.ept_caps & VMX_EPT_ADVANCED_VMEXIT_INFO_BIT)
+				mask |= EPT_VIOLATION_GVA_USER |
+					       EPT_VIOLATION_GVA_WRITABLE |
+					       EPT_VIOLATION_GVA_NX;
 			exit_qualification = fault->exit_qualification;
-			exit_qualification |= vmx_get_exit_qual(vcpu) &
-					      (EPT_VIOLATION_GVA_IS_VALID |
-					       EPT_VIOLATION_GVA_TRANSLATED);
+			exit_qualification |= vmx_get_exit_qual(vcpu) & mask;
 			vm_exit_reason = EXIT_REASON_EPT_VIOLATION;
 		}
 
@@ -7238,7 +7242,8 @@ static void nested_vmx_setup_secondary_ctls(u32 ept_caps,
 			VMX_EPT_PAGE_WALK_5_BIT |
 			VMX_EPTP_WB_BIT |
 			VMX_EPT_INVEPT_BIT |
-			VMX_EPT_EXECUTE_ONLY_BIT;
+			VMX_EPT_EXECUTE_ONLY_BIT |
+			VMX_EPT_ADVANCED_VMEXIT_INFO_BIT;
 
 		msrs->ept_caps &= ept_caps;
 		msrs->ept_caps |= VMX_EPT_EXTENT_GLOBAL_BIT |
-- 
2.53.0