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

From: Stefan Richter
Date: Sat Mar 22 2008 - 14:29:24 EST


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
-=====-==--- --== =-==-
http://arcgraph.de/sr/
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