Re: RE : Re: x86 setup code rewrite in C - revised

From: Linus Torvalds
Date: Fri Jul 13 2007 - 19:09:50 EST




On Fri, 13 Jul 2007, Etienne Lorrain wrote:
>
> > >> Also, I do not know if "m" is right in here:
> > >> static inline u8 rdfs8(addr_t addr)
> > >> {
> > >> u8 v;
> > >> asm("movb %%fs:%1,%0" : "=r" (v) : "m" (*(u8 *)addr));
> > >> return v;
> > >> }
> >
> > The "m" is correct right there.
>
> strange, "g" would mean anything can go there - and this assembly instruction
> should accept every access modes.

No it damn well should NOT.

the %fs: override works only with memory ops. End of story.

Linus
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