linux-kernel - Re: [PATCH] x86: static_cpu_has_safe: discard dynamic check after init

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Message-ID: <20160116193658.GC32085@pd.tnic>
Date:	Sat, 16 Jan 2016 20:36:58 +0100
From:	Borislav Petkov <bp@...e.de>
To:	Brian Gerst <brgerst@...il.com>
Cc:	x86@...nel.org, linux-kernel@...r.kernel.org,
	Ingo Molnar <mingo@...nel.org>,
	"H. Peter Anvin" <hpa@...or.com>,
	Denys Vlasenko <dvlasenk@...hat.com>,
	Andy Lutomirski <luto@...capital.net>,
	Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: [PATCH] x86: static_cpu_has_safe: discard dynamic check after
 init

On Sat, Jan 16, 2016 at 02:22:04PM -0500, Brian Gerst wrote:
> Move the code to do the dynamic check to the init text section so that it
> is discarded after alternatives have run and a static branch has been
> chosen.
> 
> A new section is defined to avoid warnings with modpost due to references
> to init text from main text, which in this case is legitimate.  All such
> references are patched out before init mem is discarded.

And we're doing this because...? Space savings? How much are we talkin'?

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--