Re: Patch "page-allocator: preserve PFN ordering when __GFP_COLD is set" fails on my system

[Juergen Beisert <jbe@pengutronix.de>]

On Mittwoch, 12. August 2009, Mel Gorman wrote:
> > > I get the following Ooops message when "udevadm" is running on an ARM
> > > S3C2440 CPU based system:
>
> This is extremely odd. All that patch is doing is changing what order pages
> are returned in to the caller when __GFP_COLD is specified.  valid memory.
> Does reverting the patch really make the problem go away?

At least I can work with the system if I remove this patch. Theres is no oops, 
so udev creates all the required devnodes and the system comes up into the 
login prompt.

> > > [...]
> > > starting udevd...done
> > > Unable to handle kernel paging request at virtual address e3540000
> > > pgd = c39d4000
> > > [e3540000] *pgd\0000000
> > > Internal error: Oops: 5 [#1]
> > > Modules linked in:
> > > CPU: 0    Not tainted  (2.6.31-rc4-00296-ge084b2d-dirty #10)
> > > PC is at strlen+0xc/0x20
> > > LR is at kobject_get_path+0x24/0xa4
>
> I haven't tackled this sort of bug before but it looks more likely that
> there is garbage in the sysfs tree that is being tripped up on.

Yes, I think so, too. Because the same binary rc5 image runs on an S3C2410 CPU 
without an oops, but oopses on an S3C2440 (both CPUs are nearly the same, but 
only nearly). But how to track down such a failure?

Regards,
Juergen

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