Re: [PATCH 1/1] Speedfreq-SMI call clobbers ECX

Ingo Molnar
2008-03-05T15:35:49Z

* Stephan Diestelhorst <langer_mann@web.de> wrote:

> @@ -184,7 +184,7 @@ static void speedstep_set_state (unsigne
> __asm__ __volatile__(
> "movl $0, %%edi\n"
> "out %%al, (%%dx)\n"
> - : "=b" (new_state), "=D" (result)
> + : "=b" (new_state), "=D" (result), "=c" (ecx_clobber)
> : "a" (command), "b" (function), "c" (state), "d" (smi_port), "S" (0)
> );

stupid suggestion: why not do a pusha/popa around those instructions, to
make sure everything is restored? This isnt a fastpath and being
conservative about SMI side-effects cannot hurt ...

Ingo