Re: pnp changes -> suspend oops [Was: 2.6.26-rc5-mm2]

Jiri Slaby
2008-06-12T21:11:30Z

On 06/11/2008 09:03 PM, Bjorn Helgaas wrote:
> On Wednesday 11 June 2008 12:08:53 pm Jiri Slaby wrote:
>> On 06/10/2008 07:31 AM, Andrew Morton wrote:
>>> ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.26-rc5/2.6.26-rc5-mm2/
>> I face problems after some of the pnp changes. If this is not known, I may
>> bisect it, it's 100% reproducible. I have no real logs, It panics prior to
>> network is woken up to see something on netconsole, I just captured a function
>> name and an offset of place where it oopses.
>>
>> pnpacpi_encode_resources, ACPI_RESOURCE_TYPE_DMA case, pnp_get_resource(dev,
>> IORESOURCE_DMA, dma) returns NULL, which is dereferenced at pnpacpi_encode_dma
>> at p->flags.
>>
>> It happens on resume after mem > /sys/power/state.
>
> Thanks for the report, I hadn't heard about this.
>
> We used to always have a resource from the static table to encode
> (assuming the table was big enough), even if that resource was
> disabled or unassigned. But now we don't keep those around, so
> we can end up with null pointers like you're seeing.
>
> Before you go to all the trouble of bisecting it, can you turn on
> CONFIG_PNP_DEBUG and try the following debug patch? I think this
> will prevent the oops, but it's just papering over the real problem,
> so please capture the complete dmesg log.

ACPI: PCI interrupt for device 0000:00:02.0 disabled
serial 00:07: disabled
serial 00:06: disabled
ACPI handle has no context!
ACPI: PCI interrupt for device 0000:00:1d.7 disabled
...
serial 00:06: no dma resource to encode!
serial 00:06: activated
serial 00:07: no dma resource to encode!
serial 00:07: activated
ACPI: PCI Interrupt 0000:00:02.0[A] -> GSI 16 (level, low) -> IRQ 16