Re: [PATCH 1/5] resources: add arch hook for preventing allocation in reserved areas

Jesse Barnes
2010-12-11T01:37:49Z

On Fri, 10 Dec 2010 14:07:24 -0700
Bjorn Helgaas <bjorn.helgaas@hp.com> wrote:

> On Friday, December 10, 2010 01:36:09 pm Jesse Barnes wrote:
> > [Actually cc'ing Matthew this time]
> >
> > On Fri, 10 Dec 2010 12:30:08 -0800
> > Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
> >
> > > On Wed, 08 Dec 2010 14:36:06 -0700
> > > Bjorn Helgaas <bjorn.helgaas@hp.com> wrote:
> > >
> > > >
> > > > This adds arch_remove_reservations(), which an arch can implement if it
> > > > needs to protect part of the address space from allocation.
> > > >
> > > > Sometimes that can be done by just requesting a resource. This hook is to
> > > > cover cases where protected area doesn't fit well in the hierarchical
> > > > resource tree. For example, x86 BIOS E820 reservations are not related
> > > > to devices, so they may overlap part of, all of, or more than a device
> > > > resource.
> > > >
> > > > Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
> > > > ---
> > >
> > > Hm, this is bigger than the simple change of just avoiding the high 2M;
> > > Linus have you checked it out yet? It's nicer than simply adjusting
> > > PCIBIOS_MAX_MEM since it will affect all resource callers rather than
> > > just PCI, but it's definitely bigger.
>
> Dan Williams also reproduced the problem on a 2530p and tested this
> series (though I think he actually tested a backport in Fedora):
> https://bugzilla.kernel.org/show_bug.cgi?id=23542#c7
> https://bugzilla.kernel.org/show_bug.cgi?id=23542#c23
>
> The simple PCIBIOS_MAX_MEM_32 change below will fix the 2530p problem,
> but it won't help fix the nx6325 problem Rafael reported; details at:
> https://bugzilla.kernel.org/show_bug.cgi?id=23332#c20
>
> Rafael did confirm on #acpi Wednesday that the full series fixed
> his nx6325.

Thanks, I'll add Dan and Rafael's tested-bys to the patches (they're
already in my for-linus tree). Unless Linus has a problem with them
I'll send them over to him this weekend or Monday.

--
Jesse Barnes, Intel Open Source Technology Center