KVM: nVMX: propagate errors from prepare_vmcs02
It is possible that prepare_vmcs02 fails to load the guest state. This
patch adds the proper error handling for such a case. L1 will receive
an INVALID_STATE vmexit with the appropriate exit qualification if it
happens.
A failure to set guest CR3 is the only error propagated from prepare_vmcs02
at the moment.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index bcad2eb..39a389f 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -9976,8 +9976,11 @@
* needs. In addition to modifying the active vmcs (which is vmcs02), this
* function also has additional necessary side-effects, like setting various
* vcpu->arch fields.
+ * Returns 0 on success, 1 on failure. Invalid state exit qualification code
+ * is assigned to entry_failure_code on failure.
*/
-static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
+static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
+ unsigned long *entry_failure_code)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
u32 exec_control;
@@ -10306,8 +10309,12 @@
nested_ept_enabled) {
vcpu->arch.cr3 = vmcs12->guest_cr3;
__set_bit(VCPU_EXREG_CR3, (ulong *)&vcpu->arch.regs_avail);
- } else
- kvm_set_cr3(vcpu, vmcs12->guest_cr3);
+ } else {
+ if (kvm_set_cr3(vcpu, vmcs12->guest_cr3)) {
+ *entry_failure_code = ENTRY_FAIL_DEFAULT;
+ return 1;
+ }
+ }
kvm_mmu_reset_context(vcpu);
@@ -10326,6 +10333,7 @@
kvm_register_write(vcpu, VCPU_REGS_RSP, vmcs12->guest_rsp);
kvm_register_write(vcpu, VCPU_REGS_RIP, vmcs12->guest_rip);
+ return 0;
}
/*
@@ -10340,6 +10348,7 @@
struct loaded_vmcs *vmcs02;
bool ia32e;
u32 msr_entry_idx;
+ unsigned long exit_qualification;
if (!nested_vmx_check_permission(vcpu))
return 1;
@@ -10502,7 +10511,13 @@
vmx_segment_cache_clear(vmx);
- prepare_vmcs02(vcpu, vmcs12);
+ if (prepare_vmcs02(vcpu, vmcs12, &exit_qualification)) {
+ leave_guest_mode(vcpu);
+ vmx_load_vmcs01(vcpu);
+ nested_vmx_entry_failure(vcpu, vmcs12,
+ EXIT_REASON_INVALID_STATE, exit_qualification);
+ return 1;
+ }
msr_entry_idx = nested_vmx_load_msr(vcpu,
vmcs12->vm_entry_msr_load_addr,