KVM: x86 emulator: fix in/out emulation.
in/out emulation is broken now. The breakage is different depending
on where IO device resides. If it is in userspace emulator reports
emulation failure since it incorrectly interprets kvm_emulate_pio()
return value. If IO device is in the kernel emulation of 'in' will do
nothing since kvm_emulate_pio() stores result directly into vcpu
registers, so emulator will overwrite result of emulation during
commit of shadowed register.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b99cec1..776d3e2 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -590,8 +590,7 @@
struct x86_emulate_ctxt;
-int kvm_emulate_pio(struct kvm_vcpu *vcpu, int in,
- int size, unsigned port);
+int kvm_fast_pio_out(struct kvm_vcpu *vcpu, int size, unsigned short port);
int kvm_emulate_pio_string(struct kvm_vcpu *vcpu, int in,
int size, unsigned long count, int down,
gva_t address, int rep, unsigned port);