From 0912c9771e9902f752e890e93af495cc06a786ac Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 27 Aug 2013 15:41:43 +0200 Subject: [PATCH] KVM: x86: add comments where MMIO does not return to the emulator Support for single-step in the emulator (new in 3.12) does not work for MMIO or PIO writes, because they are completed without returning to the emulator. This is not worse than what we had in 3.11; still, add comments so that the issue is not forgotten. Signed-off-by: Paolo Bonzini Signed-off-by: Gleb Natapov --- arch/x86/kvm/x86.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index cb276e976203..e514b3cb8b93 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5122,9 +5122,10 @@ restart: inject_emulated_exception(vcpu); r = EMULATE_DONE; } else if (vcpu->arch.pio.count) { - if (!vcpu->arch.pio.in) + if (!vcpu->arch.pio.in) { + /* FIXME: return into emulator if single-stepping. */ vcpu->arch.pio.count = 0; - else { + } else { writeback = false; vcpu->arch.complete_userspace_io = complete_emulated_pio; } @@ -6176,6 +6177,8 @@ static int complete_emulated_mmio(struct kvm_vcpu *vcpu) if (vcpu->mmio_cur_fragment == vcpu->mmio_nr_fragments) { vcpu->mmio_needed = 0; + + /* FIXME: return into emulator if single-stepping. */ if (vcpu->mmio_is_write) return 1; vcpu->mmio_read_completed = 1; -- 2.39.5