From mboxrd@z Thu Jan  1 00:00:00 1970
From: will.deacon@arm.com (Will Deacon)
Date: Mon, 3 Jun 2013 10:54:25 +0100
Subject: A bug about system call on ARM
In-Reply-To: <35FD53F367049845BC99AC72306C23D1610991B87B@CNBJMBX05.corpusers.net>
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Message-ID: <20130603095425.GA32242@mudshark.cambridge.arm.com>
To: linux-arm-kernel@lists.infradead.org
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On Mon, Jun 03, 2013 at 06:25:26AM +0100, Wang, Yalin wrote:
> Hi  Will,
> 
> I have a question about this patch .
> 
> If the user space is thumb mode,
> The PC should be rewind by 2 bytes,
> So the fix_up code should be 
> 
> Sub lr, lr, #2 .
> 
> 
> Am I right ?

No, because we don't have OABI-compat support for Thumb applications and
force everything down the EABI path instead.

Did you manage to test the patch?

Will