From: Marcelo Tosatti <mtosatti@redhat.com>
To: kvm-devel <kvm@vger.kernel.org>
Cc: Gleb Natapov <gleb@redhat.com>
Subject: KVM: x86: stop IO emulation cycle if instruction pointer is modified
Date: Fri, 5 Jul 2013 16:16:55 -0300 [thread overview]
Message-ID: <20130705191654.GA18788@amt.cnet> (raw)
MMIO/PIO emulation should be interrupted if the system is restarted.
Otherwise in progress IO emulation continues at the instruction pointer,
even after vcpus' IP has been modified by KVM_SET_REGS.
Use IP change as an indicator to reset MMIO/PIO emulation state.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e8ba99c..9f7ce41 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6144,6 +6144,10 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
kvm_register_write(vcpu, VCPU_REGS_R15, regs->r15);
#endif
+ /* stop IO emulation cycle if RIP changes */
+ if (kvm_rip_read(vcpu) != regs->rip)
+ vcpu->arch.complete_userspace_io = NULL;
+
kvm_rip_write(vcpu, regs->rip);
kvm_set_rflags(vcpu, regs->rflags);
next reply other threads:[~2013-07-05 19:39 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-05 19:16 Marcelo Tosatti [this message]
2013-07-06 7:41 ` KVM: x86: stop IO emulation cycle if instruction pointer is modified Gleb Natapov
2013-07-08 21:16 ` Marcelo Tosatti
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