Re: [git patches] libata updates for 3.3

From: Linus Torvalds
Date: Mon Jan 16 2012 - 14:47:33 EST


On Mon, Jan 16, 2012 at 11:42 AM, Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote:
>
> There are two sets of problems with that
>
> The first is that quite a few machines crap themselves if you do this
> because nobody has ever tested things like the IRQ routing or the
> firmware on suspend/resume when they find the hardwared controller has
> gone for a walk.

I think this could trivially be solved at least on these kinds of
Apple machines by just making it a config option, and just not doing
it if it doesn't work. Some kernel command line to say "ahci=force" or
whatever.

That doesn't solve the "user never even realized" problem, but at
least it gives the user the possibility of solving the "crap firmware
doesn't even allow this".

> Putting it back on suspend might help in some cases but then you get to
> pick your way through the documentation minefield, deal with device
> changes while in non AHCI mode, figure out how to set up registers the
> BIOS didn't etc.

Yeah, no, that would just be horrible. I doubt it happens in practice,
though. I bet the normal PCI/AHCI resume will just do the right
thing. But I haven't tried..

Linus
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/