Re: [PATCH] ALSA: hda-intel - Disable MSI support by default

[Jeff Garzik <jeff@garzik.org>]

Linus Torvalds wrote:
> 
> On Tue, 14 Nov 2006, Jeff Garzik wrote:
>> :(  Like AHCI, PCI MSI has -always- worked wonderfully for HD audio AFAIK.
> 
> That "AFAIK" is shorthand for "As Far As I haven't read any of the 
> bug-reports but Know", right?

None of the bug reports indicate Intel, thus following the well 
established pattern of "it works great on Intel, but not elsewhere"


>> Is a whitelist patch forthcoming?
> 
> Probably not. The advantages of MSI aren't all that obvious, and the 
> disadvantages seem to be that it just doesn't work all that well for some 
> people.
> 
> The fact that it works for MOST people has absolutely zero relevance. 
> We've had too many frigging patches that have apparently been of the "this 
> works for me, I don't care if some other motherboard has problems" kind.
> 
> See for example:
> 
> 	http://lkml.org/lkml/2006/10/7/164
> 
> and yes, that HDA MSI _does_ seem to be causing problems.

But not on Intel, hence the obvious whitelist question.


> So don't blather about "MSI never causes problems". It's broken. Please 
> stop living in denial.
> 
> When somebody can actually say what the huge advantages to MSI are that 
> it's worth using when 
> 
>  (a) several motherboards are apparently known broken

several non-Intel motherboards


>  (b) microsoft apparently is of the same opinion and _also_ doesn't use it

Yeah well, that's sage advice only when it's sage advice.  MS lags us by 
years.  We do some bleeding, on the bleeding edge.


>  (c) the old non-MSI code works fine
> 
>  (d) there is apparently no fool-proof way to tell when it works and when 
>      it doesn't.
> 
> then please holler. Btw, I'm not even _interested_ in any advantages 
> unless you also have a solution for (d). Not a "it should work". I want to 
> hear something that is _guaranteed_ to work.

if (intel) ...

That has a track record of working.

It's nice not to have to deal with shared interrupts.

	Jeff