KVM: x86: Add explicit flag for forced emulation on #UD

Add an explicit emulation type for forced #UD emulation and use it to
detect that KVM should unconditionally inject a #UD instead of falling
into its standard emulation failure handling.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2019-08-27 14:40:32 -07:00 committed by Paolo Bonzini
parent 42cbf06872
commit b400060620
2 changed files with 4 additions and 2 deletions

View File

@ -1325,6 +1325,7 @@ enum emulation_result {
#define EMULTYPE_TRAP_UD (1 << 1)
#define EMULTYPE_SKIP (1 << 2)
#define EMULTYPE_ALLOW_RETRY (1 << 3)
#define EMULTYPE_TRAP_UD_FORCED (1 << 4)
#define EMULTYPE_VMWARE_GP (1 << 5)
int kvm_emulate_instruction(struct kvm_vcpu *vcpu, int emulation_type);
int kvm_emulate_instruction_from_buffer(struct kvm_vcpu *vcpu,

View File

@ -5449,7 +5449,7 @@ int handle_ud(struct kvm_vcpu *vcpu)
sig, sizeof(sig), &e) == 0 &&
memcmp(sig, "\xf\xbkvm", sizeof(sig)) == 0) {
kvm_rip_write(vcpu, kvm_rip_read(vcpu) + sizeof(sig));
emul_type = 0;
emul_type = EMULTYPE_TRAP_UD_FORCED;
}
er = kvm_emulate_instruction(vcpu, emul_type);
@ -6629,7 +6629,8 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu,
trace_kvm_emulate_insn_start(vcpu);
++vcpu->stat.insn_emulation;
if (r != EMULATION_OK) {
if (emulation_type & EMULTYPE_TRAP_UD)
if ((emulation_type & EMULTYPE_TRAP_UD) ||
(emulation_type & EMULTYPE_TRAP_UD_FORCED))
return EMULATE_FAIL;
if (reexecute_instruction(vcpu, cr2, write_fault_to_spt,
emulation_type))