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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 10 Jan 2018 13:11:48 -0800
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Subject: Re: [PATCH] x86/alternatives: Fix optimize_nops() checking
To: David Woodhouse <dwmw2@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>,
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On Wed, Jan 10, 2018 at 1:08 PM, David Woodhouse <dwmw2@infradead.org> wrote:
>
> There are a few of the form 'call *somefunc'.
>
> The existing code handles them not by virtue of the relocs, as I said,
> but by a simple delta of the old and new location of the instruction.
>
> But it only does so for the *first* instruction of the altinstr, if it
> happens to be a (4-byte?) branch.

Ugh. That's nasty.

Wouldn't it be much better to simply do it as part of relocation instead?

                 Linus