Re: [PATCH] x86: Fix early boot crash on gcc-10, next try

From: Borislav Petkov
Date: Sat Apr 25 2020 - 14:56:09 EST


On Sat, Apr 25, 2020 at 01:37:01PM -0500, Segher Boessenkool wrote:
> That is a lot more typing then
> asm("");

That's why a macro with a hopefully more descriptive name would be
telling more than a mere asm("").

> but more seriously, you probably should explain why you do not want a
> tail call *anyway*, and in such a comment you can say that is what the
> asm is for.

Yes, the final version will have a comment and the whole spiel. This
diff is just me polling the maintainers: "do you want this for your arch
too?" Well, the PPC maintainers only, actually.

The other call in init/main.c would be for everybody.

> I don't see anything that prevents the tailcall in current code either,
> fwiw.

Right, and I don't see a reason why gcc-10 would do that optimization on
x86 only but I better ask first.

Thx.

--
Regards/Gruss,
Boris.

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