Subject: RE: [microblaze-uclinux] [PATCH v2] microblaze: nommu: Don't
 clobber R11 on syscalls
From: "Steven J. Magnani" <steve@digidescorp.com>
Reply-To: steve@digidescorp.com
To: microblaze-uclinux@itee.uq.edu.au
Cc: linux-kernel@vger.kernel.org, monstr@monstr.eu
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Organization: Digital Design Corporation
Date: Mon, 14 Dec 2009 22:41:28 -0600
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On Mon, 2009-12-14 at 14:50 -0800, Jim Van Vorst wrote:
> Isn't R11 a temporary?  If it doesn't need to be preserved across function
> calls, why can't it be clobbered during a syscall?

Because the Microblaze syscall macros don't include r11 in the clobber
list. I suppose an alternative solution would just change the userspace
macros and not the kernel, even though there is a bug in the kernel. 

Michal, is the Microblaze ABI considered "locked down" now, or is a
kernel solution still permitted?

------------------------------------------------------------------------
 Steven J. Magnani               "I claim this network for MARS!
 www.digidescorp.com              Earthling, return my space modulator!"

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