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Date: Fri, 19 Feb 2010 00:38:48 +0100
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Subject: Re: [PATCH 02/10] x86: add support for relative CALL and JMP in 
	alternatives
From: Luca Barbieri <luca@luca-barbieri.com>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: mingo@elte.hu, a.p.zijlstra@chello.nl, akpm@linux-foundation.org,
       linux-kernel@vger.kernel.org
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> The existing instruction parser is only present if KPROBES is configured
> in... this patch would make it obligatory.  Your patch doesn't reflect
> that.  Furthermore, it is ~16K of code and data which probably will make
> embedded people unhappy... although perhaps isn't out of line.
Didn't notice that.

> A good question, though, is if we actually need support for JMP or CALL
> as anything but the first instruction (usually the *only* instruction),
> which would make it a lot easier...

Probably not.
I think an even better option is to create a CALL if replacementlen is 0xff.
This would save some space for each callsite and make it clear we only
support this usage.