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Date: Thu, 5 Oct 2017 14:52:19 +0200 (CEST)
From: Michael Matz <matz@suse.de>
To: Borislav Petkov <bp@alien8.de>
cc: Mathias Krause <minipli@googlemail.com>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
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Subject: Re: [PATCH] x86/alternatives: Fix alt_max_short macro to really be
 a max()
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Hi,

On Thu, 5 Oct 2017, Borislav Petkov wrote:

> On Thu, Oct 05, 2017 at 02:35:33PM +0200, Mathias Krause wrote:
> > Note the "<"! ...comment is wrong, though the implementation works!
> 
> I know, I realized that when I looked at alternative-asm.h. Wanted to
> double-check it with Micha first.

Yeah, for bit-twiddling the result of arithmetic would need to be 
booleanized first, or alternatively the boolean operators be used in the 
first place.  So if '<' works then that's better in this context.

(In a different context, or in the same one there definitely was a problem 
with using '<', but I can't remember the details, it's too long ago we 
discussed about this; maybe it even was a problem only with some binutils 
versions.  So I'd suggest using the more obvious way until problems 
reoccur, and then document why exactly using relational ops was a problem 
;-) )


Ciao,
Michael.