Date: Sun, 20 Jan 2008 13:51:12 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: David Newall <davidn@davidnewall.com>
Cc: Andi Kleen <andi@firstfloor.org>, akpm@osdl.org,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH for mm] Remove iBCS support
Message-ID: <20080120135112.7bc317c7@lxorguk.ukuu.org.uk>
In-Reply-To: <47934FF5.4010904@davidnewall.com>
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> Well, I'm whispering:  The cost is that something desirable but
> incomplete would be removed.  While it's there it's a constant source of
> irritation to those in the know.  Once removed it can be forgotten.  So
> the cost is really that iBCS2 compatibility becomes less likely.  What's
> the benefit in removing it?  Up to 20 cycles per exec?  That's nothing.

Well you whispered many years too late. iBCS support vanished in 2.4
because nobody cared, nobody wanted to maintain it and not a single
vendor saw a business demand to justify assigning someone to do any work
with it.

If you want it back then you need to port the 2.4 iBCS emulation layer
code to 2.6 first. Of course you could probably  also do it all in user
space with some LD_PRELOAD work and binfmt_misc. That might be a bit
slower but a lot more portable.

Alan
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