Re: Help needed, Re: [Bug #14334] pcmcia suspend regression from 2.6.31.1 to 2.6.31.2 - Dell Inspiron 600m

From: Rafael J. Wysocki
Date: Fri Oct 30 2009 - 16:31:31 EST


On Friday 30 October 2009, Linus Torvalds wrote:
>
> On Fri, 30 Oct 2009, Rafael J. Wysocki wrote:
> >
> >
> > 1) Resume works if pcmcia_socket_dev_resume(dev) is moved to the "regular"
> > resume phase, after resume_device_irqs().
>
> Hmm. We really probably shouldn't call pcmcia_socket_dev_resume() in
> early_resume. It takes mutexes etc, and it calls "socket_resume()", which
> sleeps etc. That per se should be ok these days (since we don't actualyl
> disable CPU irq's, just device irqs), but it also does that whole card
> insertion events etc. And _that_ code I wouldn't trust at all.

I thought so when I worked on commit 0c570cdeb, but then it turned out to
work just fine with a number of boxes.

> The PCMCIA code is better than it used to be a long time ago, but some of
> it is still pretty crazy.
>
> I get the feeling that we should just revert that commit 0c570cdeb,

Well, there's nothing wrong with doing the PCI stuff and restoring the state at
the _noirq stage IMO, so instead of reverting it altogether, I'd add
yenta_dev_suspend|resume() that would just call
pcmcia_socket_dev_suspend|resume() during "regular" suspend|resume.

> and instead always do PCMCIA suspend as a "eject" event. That way we have no
> driver behind it to resume at resume time - and we'll see any plugged-in
> device as just a new insertion.

In fact I thought about that.

It looks like I need to find a CardBus adapter somewhere and clean that thing up.

That said, I'd really like to know what's going on in there. :-)

Thanks,
Rafael
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