Merge branch 'kvm-fixes' into 'next'

[platform/kernel/linux-rpi.git] / arch / x86 / kvm / vmx / vmx.c

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 544a35b..7558967 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -128,6 +128,9 @@ static bool __read_mostly enable_preemption_timer = 1;
 module_param_named(preemption_timer, enable_preemption_timer, bool, S_IRUGO);
 #endif
 
+extern bool __read_mostly allow_smaller_maxphyaddr;
+module_param(allow_smaller_maxphyaddr, bool, S_IRUGO);
+
 #define KVM_VM_CR0_ALWAYS_OFF (X86_CR0_NW | X86_CR0_CD)
 #define KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST X86_CR0_NE
 #define KVM_VM_CR0_ALWAYS_ON                           \
@@ -834,6 +837,18 @@ void update_exception_bitmap(struct kvm_vcpu *vcpu)
         */
        if (is_guest_mode(vcpu))
                eb |= get_vmcs12(vcpu)->exception_bitmap;
+        else {
+               /*
+                * If EPT is enabled, #PF is only trapped if MAXPHYADDR is mismatched
+                * between guest and host.  In that case we only care about present
+                * faults.  For vmcs02, however, PFEC_MASK and PFEC_MATCH are set in
+                * prepare_vmcs02_rare.
+                */
+               bool selective_pf_trap = enable_ept && (eb & (1u << PF_VECTOR));
+               int mask = selective_pf_trap ? PFERR_PRESENT_MASK : 0;
+               vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK, mask);
+               vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH, mask);
+       }
 
        vmcs_write32(EXCEPTION_BITMAP, eb);
 }
@@ -4363,16 +4378,6 @@ static void init_vmcs(struct vcpu_vmx *vmx)
                vmx->pt_desc.guest.output_mask = 0x7F;
                vmcs_write64(GUEST_IA32_RTIT_CTL, 0);
        }
-
-       /*
-        * If EPT is enabled, #PF is only trapped if MAXPHYADDR is mismatched
-        * between guest and host.  In that case we only care about present
-        * faults.
-        */
-       if (enable_ept) {
-               vmcs_write32(PAGE_FAULT_ERROR_CODE_MASK, PFERR_PRESENT_MASK);
-               vmcs_write32(PAGE_FAULT_ERROR_CODE_MATCH, PFERR_PRESENT_MASK);
-       }
 }
 
 static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
@@ -4814,6 +4819,7 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu)
                         * EPT will cause page fault only if we need to
                         * detect illegal GPAs.
                         */
+                       WARN_ON_ONCE(!allow_smaller_maxphyaddr);
                        kvm_fixup_and_inject_pf_error(vcpu, cr2, error_code);
                        return 1;
                } else
@@ -5343,7 +5349,7 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu)
         * would also use advanced VM-exit information for EPT violations to
         * reconstruct the page fault error code.
         */
-       if (unlikely(kvm_vcpu_is_illegal_gpa(vcpu, gpa)))
+       if (unlikely(allow_smaller_maxphyaddr && kvm_vcpu_is_illegal_gpa(vcpu, gpa)))
                return kvm_emulate_instruction(vcpu, 0);
 
        return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
@@ -8008,11 +8014,12 @@ static int __init vmx_init(void)
        vmx_check_vmcs12_offsets();
 
        /*
-        * Intel processors don't have problems with
-        * GUEST_MAXPHYADDR < HOST_MAXPHYADDR so enable
-        * it for VMX by default
+        * Shadow paging doesn't have a (further) performance penalty
+        * from GUEST_MAXPHYADDR < HOST_MAXPHYADDR so enable it
+        * by default
         */
-       allow_smaller_maxphyaddr = true;
+       if (!enable_ept)
+               allow_smaller_maxphyaddr = true;
 
        return 0;
 }