From: Sean Christopherson <seanjc@xxxxxxxxxx>
Use trace_kvm_nested_vmenter_failed() and its macro magic to trace
consistency check failures on nested VMRUN. Tracing such failures by
running the buggy VMM as a KVM guest is often the only way to get a
precise explanation of why VMRUN failed.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Message-Id: <20210204000117.3303214-13-seanjc@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/svm/nested.c | 33 +++++++++++++++++++--------------
1 file changed, 19 insertions(+), 14 deletions(-)
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index cadf776f58f7..03a06f959bc8 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -29,6 +29,8 @@
#include "lapic.h"
#include "svm.h"
+#define CC KVM_NESTED_VMENTER_CONSISTENCY_CHECK
+
static void nested_svm_inject_npf_exit(struct kvm_vcpu *vcpu,
struct x86_exception *fault)
{
@@ -233,14 +235,13 @@ static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
static bool nested_vmcb_check_controls(struct vmcb_control_area *control)
{
- if ((vmcb_is_intercept(control, INTERCEPT_VMRUN)) == 0)
+ if (CC(!vmcb_is_intercept(control, INTERCEPT_VMRUN)))
return false;
- if (control->asid == 0)
+ if (CC(control->asid == 0))
return false;
- if ((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) &&
- !npt_enabled)
+ if (CC((control->nested_ctl & SVM_NESTED_CTL_NP_ENABLE) && !npt_enabled))
return false;
return true;
@@ -257,32 +258,36 @@ static bool nested_vmcb_check_cr3_cr4(struct vcpu_svm *svm,
* CR0.PG && EFER.LME.
*/
if ((save->efer & EFER_LME) && (save->cr0 & X86_CR0_PG)) {
- if (!(save->cr4 & X86_CR4_PAE) || !(save->cr0 & X86_CR0_PE) ||
- kvm_vcpu_is_illegal_gpa(vcpu, save->cr3))
+ if (CC(!(save->cr4 & X86_CR4_PAE)) ||
+ CC(!(save->cr0 & X86_CR0_PE)) ||
+ CC(kvm_vcpu_is_illegal_gpa(vcpu, save->cr3)))
return false;
}
- return kvm_is_valid_cr4(&svm->vcpu, save->cr4);
+ if (CC(!kvm_is_valid_cr4(vcpu, save->cr4)))
+ return false;
+
+ return true;
}
/* Common checks that apply to both L1 and L2 state. */
static bool nested_vmcb_valid_sregs(struct vcpu_svm *svm,
struct vmcb_save_area *save)
{
- if (!(save->efer & EFER_SVME))
+ if (CC(!(save->efer & EFER_SVME)))
return false;
- if (((save->cr0 & X86_CR0_CD) == 0 && (save->cr0 & X86_CR0_NW)) ||
- (save->cr0 & ~0xffffffffULL))
+ if (CC((save->cr0 & X86_CR0_CD) == 0 && (save->cr0 & X86_CR0_NW)) ||
+ CC(save->cr0 & ~0xffffffffULL))
return false;
- if (!kvm_dr6_valid(save->dr6) || !kvm_dr7_valid(save->dr7))
+ if (CC(!kvm_dr6_valid(save->dr6)) || CC(!kvm_dr7_valid(save->dr7)))
return false;
if (!nested_vmcb_check_cr3_cr4(svm, save))
return false;
- if (!kvm_valid_efer(&svm->vcpu, save->efer))
+ if (CC(!kvm_valid_efer(&svm->vcpu, save->efer)))
return false;
return true;
@@ -384,12 +389,12 @@ static inline bool nested_npt_enabled(struct vcpu_svm *svm)
static int nested_svm_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3,
bool nested_npt)
{
- if (kvm_vcpu_is_illegal_gpa(vcpu, cr3))
+ if (CC(kvm_vcpu_is_illegal_gpa(vcpu, cr3)))
return -EINVAL;
if (!nested_npt && is_pae_paging(vcpu) &&
(cr3 != kvm_read_cr3(vcpu) || pdptrs_changed(vcpu))) {
- if (!load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3))
+ if (CC(!load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3)))
return -EINVAL;
}
--
2.26.2
