Re: kernel/microcode.c error from new 64bit code

[Linus Torvalds]

On Sat, 21 Feb 2004, Pavel Machek wrote:
>
> > +	wrmsr(MSR_IA32_UCODE_WRITE,
> > +		(unsigned long) uci->mc->bits, 
> > +		(unsigned long) uci->mc->bits >> 16 >> 16);
> 				             ~~~~~~~~~~~~
> 
> I see what you are doing, but this is evil. At least comment /* ">> 32"
> is undefined on i386 */ ?

Sorry, but you're wrong.

">> 32" is underfined PERIOD! It has nothing to do with x86, it's a C
standards issue. It's undefined on any 32-bit architecture. (shifting by
the wordsize or bigger is simply not a defined C operation).

The above is not evil. The above is the standard way of doing this in C if 
you know the word-size is 32-bits or bigger.

		Linus
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