Re: ohci1394 problem (MMIO broken) (was 2.6.25-rc6-git6: Reported regressions from 2.6.24)

[Stefan Richter <stefanr@s5r6.in-berlin.de>]

Thomas Meyer wrote:
> Stefan Richter schrieb:
>>   - Several or all of ohci1394's MMIO reads return ~0 (all bits set
>>     to one) --- or 0 --- where different values are expected.
>>
>>   - In http://lkml.org/lkml/2008/2/23/244 we get to see a
>>     WARNING: at arch/x86/mm/ioremap.c:137 __ioremap+0xa7/0x16a()
>>     which is "WARN_ON_ONCE(page_is_ram(pfn));".
>>     After that, the failures start.
>>     But before that, "Unknown symbol" messages pop up when ohci1394
>>     is loaded.  These symbols are implemented by ieee1394 on which
>>     ohci1394 depends.
...
>> Thomas, you wrote in http://lkml.org/lkml/2008/3/17/316 that the 
>> problem resurfaced.
>>   - Are the "Unknown symbol"s still there?  These are not supposed to
>>     happen.
> No. (See explanation above).
>>   - Is the "WARNING: at arch/x86/mm/ioremap.c" still there?
> No. I couldn't reproduce this warning, yet.
> 
>>   - Can you reproduce it without the atheros driver?
> Yes.
> 
> See http://bugzilla.kernel.org/show_bug.cgi?id=10080.

Thanks.  Summary from today's bugzilla comments:
No ioremap warning, but MMIO reads still give bogus values and let 
ohci1394 fail.  ohci1394 still got the MMIO region 0x1'0000'0000 - 
0x1'0000'07ff, FWIW.  The length of the region is correct, but its 
contents bogus.
-- 
Stefan Richter
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http://arcgraph.de/sr/