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Date: Wed, 18 Jul 2007 14:31:43 -0400
From: Daniel Jacobowitz <drow@false.org>
To: Bill Gatliff <bgat@billgatliff.com>
Subject: Re: Gdbserver syscall clobber
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On Wed, Jul 18, 2007 at 12:59:42PM -0500, Bill Gatliff wrote:
> Now, I'm a little rusty on PPC asm (I've been doing a lot of ARM
> lately), but it looks to me like the kernel is setting bit 0 in CR0
> (oris r10, r10, 0x1000) a.k.a LT, but the user side is looking at CR0
> (bnslr+) bit 3 a.k.a. SO.  Or maybe the other way around, I'm not sure
> after reading Sections 1.2 and 2.1 of the Programming Environments manual.

It's not checking for restart here - userspace isn't supposed to have to.
It's probably checking for error.  Check for the bit of kernel code
that's supposed to back you up two instructions.

-- 
Daniel Jacobowitz
CodeSourcery