From: Paolo Bonzini pbonzini@redhat.com
commit 0d33b1baeb6ca7165d5ed4fdd1a8f969985e35b9 upstream.
Currently emulator_pio_in clears vcpu->arch.pio.count twice if emulator_pio_in_out performs kernel PIO. Move the clear into emulator_pio_out where it is actually necessary.
No functional change intended.
Cc: stable@vger.kernel.org Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest") Reviewed-by: Maxim Levitsky mlevitsk@redhat.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kvm/x86.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
--- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6915,10 +6915,8 @@ static int emulator_pio_in_out(struct kv vcpu->arch.pio.count = count; vcpu->arch.pio.size = size;
- if (!kernel_pio(vcpu, vcpu->arch.pio_data)) { - vcpu->arch.pio.count = 0; + if (!kernel_pio(vcpu, vcpu->arch.pio_data)) return 1; - }
vcpu->run->exit_reason = KVM_EXIT_IO; vcpu->run->io.direction = in ? KVM_EXIT_IO_IN : KVM_EXIT_IO_OUT; @@ -6964,9 +6962,16 @@ static int emulator_pio_out(struct kvm_v unsigned short port, const void *val, unsigned int count) { + int ret; + memcpy(vcpu->arch.pio_data, val, size * count); trace_kvm_pio(KVM_PIO_OUT, port, size, count, vcpu->arch.pio_data); - return emulator_pio_in_out(vcpu, size, port, (void *)val, count, false); + ret = emulator_pio_in_out(vcpu, size, port, (void *)val, count, false); + if (ret) + vcpu->arch.pio.count = 0; + + return ret; + }
static int emulator_pio_out_emulated(struct x86_emulate_ctxt *ctxt,