Re: [PATCH 2.5] ACPI_HT_ONLY acpismp=force

[Hugh Dickins]

On 25 Jun 2003, Andi Kleen wrote:
> Hugh Dickins <[e-mail]> writes:
> 
> > What's the point of bootparam "acpismp=force"?  A way to change
> > your mind if you just said "acpi=off"?  A hurdle to jump to get
> > CONFIG_ACPI_HT_ONLY to do what you ask?  2.4.18 used to need it to
> > enable HT, but not recent releases.  It can't configure in what's
> > not there, and now serves only to confuse: kill it.
> 
> There are some boxes that don't work with the new ACPI code, but need
> minimal acpi parsing for hyperthreaded CPUs etc.
> 
> To get these still to work the compatibility option is offered.
> 
> Basically it's another safety net. Of course it would be better
> to make new ACPI work everywhere, but it's quite difficult.
> For 2.4 it's better to have the fallback.

Sure, I don't contest that.  The patch isn't removing that fallback,
it's removing the need to say "acpismp=force" to get the fallback to
do anything at all - why demand both a config option and a bootparam?

And if there are yet others which go wrong with that fallback,
it allows "acpi=off" to boot on those too.

Whether that compatibility code should now be subject to this new
config option is questionable; but I don't propose to change that.

Hugh