Re: [RFC][PATCH 6/6] objtool,x86: Rewrite retpoline thunk calls

From: Peter Zijlstra
Date: Sat Feb 20 2021 - 18:05:58 EST


On Sat, Feb 20, 2021 at 06:41:01PM +0100, Borislav Petkov wrote:
> > - if we had negative alternatives objtool doesn't need to actually
> > rewrite code in this case. It could simply emit alternative entries
> > and call it a day.
>
> I don't mind the negative alt per se - I mind the implementation I saw.
> I'm sure we can come up with something nicer, like, for example, struct
> alt_instr.flags to denote that this feature is a NOT feature.

So you don't like the ~ or - on cpuid? ISTR we talked about
alt_instr::flags before, but Google isn't playing ball today so I can't
seem to find it.

I can certainly look at adding the flags thing.