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Date: Mon, 06 Feb 2006 16:01:40 -0800 (PST)
Message-Id: <20060206.160140.59716704.davem@davemloft.net>
To: sfr@canb.auug.org.au
Cc: akpm@osdl.org, linux-kernel@vger.kernel.org, torvalds@osdl.org, ak@suse.de
Subject: Re: [PATCH] compat: add compat functions for *at syscalls
From: "David S. Miller" <davem@davemloft.net>
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From: Stephen Rothwell <sfr@canb.auug.org.au>
Date: Tue, 7 Feb 2006 10:56:31 +1100

> This adds compat version of all the remaining *at syscalls
> so that the "dfd" arguments can be properly sign extended.
> 
> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

I do the sign extension with tiny stubs in arch/sparc64/kernel/sys32.S
so that the arg frobbing does not consume a stack frame, which is what
happens if you do this in C code.

We need to revisit this at some point and make a way for all
compat platforms to do this with a portable table of some kind
that expands a bunch of macros defined by the platform.