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Date: Wed, 27 Jul 2005 13:27:01 -0700 (PDT)
Message-Id: <20050727.132701.115907512.davem@davemloft.net>
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Cc: akpm@osdl.org, paulus@samba.org, linux-kernel@vger.kernel.org,
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Subject: Re: [patch] inotify: ppc64 syscalls.
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From: Robert Love <rml@novell.com>
Date: Wed, 27 Jul 2005 13:31:36 -0400

> [ I don't think we need sys32 compatibility versions--and if we do, I
> failed in life. ]

add_watch and rm_watch both do, because system call arguments are
zero-extended by default for compat tasks, thus the "fd" arg needs
sign extension.

You'll notice that sys_ppc32.c has a ton of shims which purely
exist to sign extend "int" system call arguments.  Sparc64 does
something similarly, but in assembler so that we don't eat the
overhead of a full stack frame just to sign extend arguments.