Define independent macros for the RWX protection bits that are enumerated
via EXIT_QUALIFICATION for EPT Violations, and tie them to the RWX bits in
EPT entries via compile-time asserts. Piggybacking the EPTE defines works
for now, but it creates holes in the EPT_VIOLATION_xxx macros and will
cause headaches if/when KVM emulates Mode-Based Execution (MBEC), or any
other features that introduces additional protection information.
Opportunistically rename EPT_VIOLATION_RWX_MASK to EPT_VIOLATION_PROT_MASK
so that it doesn't become stale if/when MBEC support is added.
No functional change intended.
Cc: Jon Kohler <jon@xxxxxxxxxxx>
Cc: Nikolay Borisov <nik.borisov@xxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/include/asm/vmx.h | 13 +++++++++++--
arch/x86/kvm/mmu/paging_tmpl.h | 3 +--
arch/x86/kvm/vmx/vmx.c | 2 +-
3 files changed, 13 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index aabc223c6498..8707361b24da 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -580,14 +580,23 @@ enum vm_entry_failure_code {
/*
* Exit Qualifications for EPT Violations
*/
-#define EPT_VIOLATION_RWX_SHIFT 3
#define EPT_VIOLATION_ACC_READ BIT(0)
#define EPT_VIOLATION_ACC_WRITE BIT(1)
#define EPT_VIOLATION_ACC_INSTR BIT(2)
-#define EPT_VIOLATION_RWX_MASK (VMX_EPT_RWX_MASK << EPT_VIOLATION_RWX_SHIFT)
+#define EPT_VIOLATION_PROT_READ BIT(3)
+#define EPT_VIOLATION_PROT_WRITE BIT(4)
+#define EPT_VIOLATION_PROT_EXEC BIT(5)
+#define EPT_VIOLATION_PROT_MASK (EPT_VIOLATION_PROT_READ | \
+ EPT_VIOLATION_PROT_WRITE | \
+ EPT_VIOLATION_PROT_EXEC)
#define EPT_VIOLATION_GVA_IS_VALID BIT(7)
#define EPT_VIOLATION_GVA_TRANSLATED BIT(8)
+#define EPT_VIOLATION_RWX_TO_PROT(__epte) (((__epte) & VMX_EPT_RWX_MASK) << 3)
+
+static_assert(EPT_VIOLATION_RWX_TO_PROT(VMX_EPT_RWX_MASK) ==
+ (EPT_VIOLATION_PROT_READ | EPT_VIOLATION_PROT_WRITE | EPT_VIOLATION_PROT_EXEC));
+
/*
* Exit Qualifications for NOTIFY VM EXIT
*/
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index f4711674c47b..68e323568e95 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -510,8 +510,7 @@ static int FNAME(walk_addr_generic)(struct guest_walker *walker,
* Note, pte_access holds the raw RWX bits from the EPTE, not
* ACC_*_MASK flags!
*/
- walker->fault.exit_qualification |= (pte_access & VMX_EPT_RWX_MASK) <<
- EPT_VIOLATION_RWX_SHIFT;
+ walker->fault.exit_qualification |= EPT_VIOLATION_RWX_TO_PROT(pte_access);
}
#endif
walker->fault.address = addr;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index b71392989609..049f28f1b2bc 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5821,7 +5821,7 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu)
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)
+ error_code |= (exit_qualification & EPT_VIOLATION_PROT_MASK)
? PFERR_PRESENT_MASK : 0;
if (error_code & EPT_VIOLATION_GVA_IS_VALID)
--
2.48.1.711.g2feabab25a-goog
