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Date: Fri, 4 Oct 2002 15:44:05 -0600
From: "Brian F. G. Bidulock" <bidulock@openss7.org>
To: "David S. Miller" <davem@redhat.com>
Cc: alan@lxorguk.ukuu.org.uk, linux-kernel@vger.kernel.org
Subject: Re: export of sys_call_table
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David,

How many other architecture-specific exported symbols are there?

It appears to me that many of the system calls themselves are
architecture-specific, particularly so where 64-bit machines
are involved.  Is that a reason to not make them accessible?

--brian

On Fri, 04 Oct 2002, David S. Miller wrote:

>    From: Alan Cox <alan@lxorguk.ukuu.org.uk>
>    Date: 03 Oct 2002 23:02:40 +0100
>    
>    Overwriting syscall table entries is not safe. Its not safe because
>    there is no locking mechanism, and its not safe because of the pentium
>    III errata.
> 
> It is also non-portable, such syscall overwriting requires knowledge
> of the layout of the table on every architecture.  On some platforms
> it is a list of pointers + argument count, on some 64-bit platforms
> it is a list of 32-bit truncated pointers to save space.
> 
> There is simply no portable way to make changes to the system call
> table, so exporting it makes zero sense.

-- 
Brian F. G. Bidulock    ? The reasonable man adapts himself to the ?
bidulock@openss7.org    ? world; the unreasonable one persists in  ?
http://www.openss7.org/ ? trying  to adapt the  world  to himself. ?
                        ? Therefore  all  progress  depends on the ?
                        ? unreasonable man. -- George Bernard Shaw ?
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