[PATCH v2 11/13] KVM: x86: Add helper to "handle" internal emulation error

Sean Christopherson
2020-02-18T23:30:14Z

Add a helper to set the appropriate error codes in vcpu->run when
emulation fails (future patches will add additional failure scenarios).

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/x86.c | 32 ++++++++++++++------------------
1 file changed, 14 insertions(+), 18 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e1eaca65756b..7bffdc6f9e1b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6491,6 +6491,14 @@ void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip)
}
EXPORT_SYMBOL_GPL(kvm_inject_realmode_interrupt);

+static int internal_emulation_error(struct kvm_vcpu *vcpu)
+{
+ vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+ vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
+ vcpu->run->internal.ndata = 0;
+ return 0;
+}
+
static int handle_emulation_failure(struct x86_emulate_ctxt *ctxt,
int emulation_type)
{
@@ -6504,21 +6512,13 @@ static int handle_emulation_failure(struct x86_emulate_ctxt *ctxt,
return 1;
}

- if (emulation_type & EMULTYPE_SKIP) {
- vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
- vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
- vcpu->run->internal.ndata = 0;
- return 0;
- }
+ if (emulation_type & EMULTYPE_SKIP)
+ return internal_emulation_error(vcpu);

kvm_queue_exception(vcpu, UD_VECTOR);

- if (!is_guest_mode(vcpu) && kvm_x86_ops->get_cpl(vcpu) == 0) {
- vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
- vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
- vcpu->run->internal.ndata = 0;
- return 0;
- }
+ if (!is_guest_mode(vcpu) && kvm_x86_ops->get_cpl(vcpu) == 0)
+ return internal_emulation_error(vcpu);

return 1;
}
@@ -8986,12 +8986,8 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int idt_index,

ret = emulator_task_switch(ctxt, tss_selector, idt_index, reason,
has_error_code, error_code);
- if (ret) {
- vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
- vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
- vcpu->run->internal.ndata = 0;
- return 0;
- }
+ if (ret)
+ return internal_emulation_error(vcpu);

kvm_rip_write(vcpu, ctxt->eip);
kvm_set_rflags(vcpu, ctxt->eflags);
--
2.24.1