| From | Greg Kroah-Hartman <> | Subject | [PATCH 5.14 112/169] KVM: x86: leave vcpu->arch.pio.count alone in emulator_pio_in_out | Date | Mon, 25 Oct 2021 21:14:53 +0200 |
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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,
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