Re: [PATCH] KVM: Qemu: push_nmi should be only used by I386 Arch.

[Jan Kiszka <jan.kiszka@siemens.com>]

Zhang, Xiantao wrote:
> From 1b89616f99abc8e0983ef58a1f984f31a52fe828 Mon Sep 17 00:00:00 2001
> From: Xiantao Zhang <xiantao.zhang@intel.com>
> Date: Thu, 27 Nov 2008 17:24:51 +0800
> Subject: [PATCH] KVM: Qemu: push_nmi should be only used by I386 Arch.
> 
> Use TARGET_I386 to exclude other archs.
> Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
> ---
>  qemu/qemu-kvm.c |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)
> 
> diff --git a/qemu/qemu-kvm.c b/qemu/qemu-kvm.c
> index cf0e85d..b6c8288 100644
> --- a/qemu/qemu-kvm.c
> +++ b/qemu/qemu-kvm.c
> @@ -154,10 +154,12 @@ static int try_push_interrupts(void *opaque)
>      return kvm_arch_try_push_interrupts(opaque);
>  }
>  
> +#ifdef TARGET_I386
>  static void push_nmi(void *opaque)
>  {
>      kvm_arch_push_nmi(opaque);
>  }
> +#endif
>  
>  static void post_kvm_run(void *opaque, void *data)
>  {
> @@ -742,7 +744,9 @@ static struct kvm_callbacks qemu_kvm_ops = {
>      .shutdown = kvm_shutdown,
>      .io_window = kvm_io_window,
>      .try_push_interrupts = try_push_interrupts,
> +#ifdef TARGET_I386
>      .push_nmi = push_nmi,
> +#endif
>      .post_kvm_run = post_kvm_run,
>      .pre_kvm_run = pre_kvm_run,
>  #ifdef TARGET_I386

Well, doesn't push_nmi() from libkvm.c call into this hook
unconditionally if KVM_CAP_NMI is set (which is the case for all recent
kernel headers)? That should cause SEGVs, so you need to patch kvm_run()
as well.

Makes me wonder if we shouldn't have better defined KVM_CAP_NMI
conditionally, only for arch that actually have NMIs (/wrt KVM: only x86
ATM). But now it's too late...

Jan

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