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From: Peter Maydell <peter.maydell@linaro.org>
Date: Sat, 6 Jul 2013 11:24:39 +0100
Message-ID: <CAFEAcA_bep5Jk5STVbex5sapz2wHz+5Og96DTisox+pvnwgaTg@mail.gmail.com>
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Subject: Re: [Qemu-devel] [PATCH 2/9] linux-user: Add is_write segfault
	check for ARM hosts
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To: Alexander Graf <agraf@suse.de>
Cc: Riku Voipio <riku.voipio@linaro.org>, qemu-devel@nongnu.org

On 6 July 2013 01:36, Alexander Graf <agraf@suse.de> wrote:
> When we get a segmentation fault we check whether the fault was a write. If
> it was a write, it might be a fault because we tried to modify a code region.
>
> This logic does not work on ARM hosts, because they don't evaluate whether a
> segementation fault is due to a write. Instead they always declare it a read.
>
> So self modifying code fails with a segmentation fault whenever it tries to
> modify itself.
>
> Add the is_write evaluation based on what the kernel tells us as fault reason.
>
> Signed-off-by: Alexander Graf <agraf@suse.de>

We've already got a patch for this on list :
http://patchwork.ozlabs.org/patch/248590/

thanks
-- PMM