From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Date: Wed, 24 May 2006 22:02:55 +0000
Subject: Re: sigreturn on sparc64
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List-Id: <sparclinux.vger.kernel.org>
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To: sparclinux@vger.kernel.org

David Miller wrote:
> The stub is "returned to" directly from the signal handler itself
> using the "retl" instruction, which jumps to the value of "register
> %i7 plus 8".  We stick the passed in stub address directly into the
> %i7 register of the signal handler frame, that's why you need to
> subtract 8 for the system call argument.

Yup, there are a lot of things like this in the Linux ABI (something which makes sense on 
one architecture, but not across architectures); sigreturn is obviously the worst.

	-hpa