From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:54010)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <rth7680@gmail.com>) id 1V242d-0003Gn-GE
	for qemu-devel@nongnu.org; Wed, 24 Jul 2013 14:44:10 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <rth7680@gmail.com>) id 1V242Y-0007yr-JB
	for qemu-devel@nongnu.org; Wed, 24 Jul 2013 14:44:03 -0400
Received: from mail-ye0-x22d.google.com ([2607:f8b0:4002:c04::22d]:54152)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <rth7680@gmail.com>) id 1V242Y-0007yg-EG
	for qemu-devel@nongnu.org; Wed, 24 Jul 2013 14:43:58 -0400
Received: by mail-ye0-f173.google.com with SMTP id m7so3001030yen.32
	for <qemu-devel@nongnu.org>; Wed, 24 Jul 2013 11:43:58 -0700 (PDT)
Sender: Richard Henderson <rth7680@gmail.com>
Message-ID: <51F02069.8050301@twiddle.net>
Date: Wed, 24 Jul 2013 08:43:53 -1000
From: Richard Henderson <rth@twiddle.net>
MIME-Version: 1.0
References: <1374649831-5656-1-git-send-email-riku.voipio@linaro.org>
In-Reply-To: <1374649831-5656-1-git-send-email-riku.voipio@linaro.org>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [RFC] [PATCH] linux-user: implement m68k atomic
 syscalls
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: riku.voipio@linaro.org
Cc: qemu-devel@nongnu.org, Laurent Vivier <laurent@vivier.eu>

On 07/23/2013 09:10 PM, riku.voipio@linaro.org wrote:
> +#ifdef TARGET_NR_atomic_cmpxchg_32
> +    case TARGET_NR_atomic_cmpxchg_32:
> +    {
> +        /* should use start_exclusive from main.c */
> +        abi_ulong mem_value;
> +        if (get_user_u32(mem_value, arg6))
> +            ret = -TARGET_EFAULT;
> +        if (mem_value == arg2)
> +            put_user_u32(arg1, arg6);
> +        ret = mem_value;
> +        break;
> +    }

The ret = -TARGET_FAULT doesn't do anything useful
without an associated break.

The kernel queues the expected SIGSEGV for this sort
of failure.  Would that happen here?


r~