KVM: Purify x86_decode_insn() error case management
The only valid case is on protected page access, other cases are errors.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 2d55bab..888b092 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -1251,7 +1251,7 @@
u16 error_code,
int no_decode)
{
- int r = 0;
+ int r;
vcpu->mmio_fault_cr2 = cr2;
kvm_x86_ops->cache_regs(vcpu);
@@ -1294,10 +1294,14 @@
get_segment_base(vcpu, VCPU_SREG_FS);
r = x86_decode_insn(&vcpu->emulate_ctxt, &emulate_ops);
+ if (r) {
+ if (kvm_mmu_unprotect_page_virt(vcpu, cr2))
+ return EMULATE_DONE;
+ return EMULATE_FAIL;
+ }
}
- if (r == 0)
- r = x86_emulate_insn(&vcpu->emulate_ctxt, &emulate_ops);
+ r = x86_emulate_insn(&vcpu->emulate_ctxt, &emulate_ops);
if (vcpu->pio.string)
return EMULATE_DO_MMIO;