From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:43380)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <pbonzini@redhat.com>) id 1ZDBjA-0003Th-Fo
	for qemu-devel@nongnu.org; Thu, 09 Jul 2015 09:19:01 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <pbonzini@redhat.com>) id 1ZDBj7-0007xi-AH
	for qemu-devel@nongnu.org; Thu, 09 Jul 2015 09:19:00 -0400
Received: from mx1.redhat.com ([209.132.183.28]:44096)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <pbonzini@redhat.com>) id 1ZDBj7-0007xW-4j
	for qemu-devel@nongnu.org; Thu, 09 Jul 2015 09:18:57 -0400
References: <1436429849-18052-1-git-send-email-rth@twiddle.net>
	<1436429849-18052-6-git-send-email-rth@twiddle.net>
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <559E74BD.8050503@redhat.com>
Date: Thu, 9 Jul 2015 15:18:53 +0200
MIME-Version: 1.0
In-Reply-To: <1436429849-18052-6-git-send-email-rth@twiddle.net>
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH 05/14] target-i386: Enable control
	registers for MPX
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Richard Henderson <rth@twiddle.net>, qemu-devel@nongnu.org
Cc: ehabkost@redhat.com



On 09/07/2015 10:17, Richard Henderson wrote:
> 
> +void cpu_sync_bndcs_hf(CPUX86State *env)

s/hf/hflags/ :)

> +{
> +    uint32_t hflags = env->hflags;
> +    uint32_t bndcsr;
> +
> +    if ((hflags & HF_CPL_MASK) == 3) {
> +        bndcsr = env->bndcs_regs.cfgu;
> +    } else {
> +        bndcsr = env->msr_bndcfgs;
> +    }
> +
> +    if ((hflags & HF_OSXSAVE_MASK)
> +        && (env->xcr0 & XSTATE_BNDCSR)
> +        && (bndcsr & BNDCFG_ENABLE)) {
> +        hflags |= HF_MPX_EN_MASK;
> +    } else {
> +        hflags &= ~HF_MPX_EN_MASK;
> +    }
> +
> +    if (bndcsr & BNDCFG_BNDPRESERVE) {
> +        hflags |= HF_MPX_PR_MASK;
> +    } else {
> +        hflags &= ~HF_MPX_PR_MASK;
> +    }
> +
> +    env->hflags = hflags;
> +}

> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index f057982..27ae029 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -2186,6 +2186,11 @@ int kvm_arch_get_registers(CPUState *cs)
>      if (ret < 0) {
>          return ret;
>      }
> +
> +    /* ??? HFLAGS may be out of sync if any of the above error out.
> +       But there seems little point in recomputing this multiple times.  */
> +    cpu_sync_bndcs_hf(&cpu->env);

Why aren't you just using a goto, like

    if (ret < 0) {
        goto out;
    }
    ret = 0;
out:
    cpu_sync_bndcs_hf(&cpu->env);
    return ret;

>      return 0;