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Date: Fri, 13 Jul 2007 16:09:24 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Etienne Lorrain <etienne_lorrain@yahoo.fr>
cc: "H. Peter Anvin" <hpa@zytor.com>, Chuck Ebbert <cebbert@redhat.com>,
       linux-kernel@vger.kernel.org
Subject: Re: RE : Re: x86 setup code rewrite in C - revised
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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