[Qemu-devel] Re: [PATCH 07/15] kvm: Separate TCG from KVM cpu execution

[Marcelo Tosatti <mtosatti@redhat.com>]

On Mon, Feb 07, 2011 at 12:19:18PM +0100, Jan Kiszka wrote:
> Mixing up TCG bits with KVM already led to problems around eflags
> emulation on x86. Moreover, quite some code that TCG requires on cpu
> enty/exit is useless for KVM. So dispatch between tcg_cpu_exec and
> kvm_cpu_exec as early as possible.
> 
> The core logic of cpu_halted from cpu_exec is added to
> kvm_arch_process_irqchip_events. Moving away from cpu_exec makes
> exception_index meaningless for KVM, we can simply pass the exit reason
> directly (only "EXCP_DEBUG vs. rest" is relevant).
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>  cpu-exec.c        |   19 ++++++-------------
>  cpus.c            |   10 +++++-----
>  kvm-all.c         |   19 +++++++++----------
>  target-i386/kvm.c |    6 +++---
>  4 files changed, 23 insertions(+), 31 deletions(-)
> 
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index ba183c4..377a0a3 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -1502,12 +1502,13 @@ int kvm_arch_post_run(CPUState *env, struct kvm_run *run)
>  
>  int kvm_arch_process_irqchip_events(CPUState *env)
>  {
> +    if (env->interrupt_request & (CPU_INTERRUPT_HARD | CPU_INTERRUPT_NMI)) {
> +        env->halted = 0;
> +    }

Why is it necessary to clear env->halted here?