Re: Linux 2.6.23.12

[Bjorn Helgaas <bjorn.helgaas@hp.com>]

On Wednesday 09 January 2008 08:49:52 pm Greg KH wrote:
> On Wed, Jan 02, 2008 at 01:42:23PM -0700, Bjorn Helgaas wrote:
> > The patch below was put in 2.6.23.12 as a fix for
> > http://bugzilla.kernel.org/show_bug.cgi?id=9514.  It apparently
> > does make 9514 go away, but only by coincidence.  There are a
> > couple other ideas about fixing 9514.  My proposed patch is
> > attached in the bugzilla.
> > 
> > The .12 patch reduces the number of resources we reserve from
> > 24 to 8 ioport regions and from 12 to 4 mmio regions per PNP device.
> > It also removes a warning about regions we ignore.
> 
> That patch was merely a revert of a prior patch, it did not "do"
> anything new at all :)
> 
> > Obviously, we want to reserve ALL the regions for PNP devices,
> > and Thomas is working on a patch for that (which I hope will be
> > ready for 2.6.25).  But in the meantime, the .12 patch makes it
> > more likely that we will have resource conflicts with PNP devices.
> > 
> > http://bugzilla.kernel.org/show_bug.cgi?id=9630 appears to be
> > such a conflict.
> > 
> > I think the patch below should be removed from the stable series.
> 
> What do you mean "removed"?  It was a revert of a prior patch, as this
> patch was reported to cause real problems.
> 
> Do you want me to add it back, and then add another patch?  If so, can
> you please send the requested patches to stable@kernel.org so I can do
> it?

Stepping back, the biggest part of the problem is that I replaced the
ACPI motherboard driver, which reserved all resources, with the PNP
motherboard driver, which currently can reserve only a limited number
of resources, because I didn't realize that restriction.

So we've had a variety of problems, and we've tried to address them
with hacks like increasing the PNP limits.  I think we need to put
back the ACPI motherboard driver until we have dynamic PNP resources.
We will also need an it87 change to deal with
http://bugzilla.kernel.org/show_bug.cgi?id=9514.

I'll work these up and post them soon.

Bjorn