Re: + proc-dont-lock-task_structs-indefinitely-cpuset-fix-2.patch added to -mm tree

[Paul Jackson <pj@sgi.com>]

Updated and corrected results, now including the previously untested patch:

cpufreq-_ppc-frequency-change-issues-freq-already-lowered-by-bios.patch - good
gregkh-driver-put_device-might_sleep.patch                              - special case
gregkh-driver-empty_release_functions_are_broken.patch                  - special case
gregkh-driver-allow-sysfs-attribute-files-to-be-pollable.patch          - bad

where the two special cases boot with the warnings reported,
and the bad case crashes on boot as reported.

That a patch named "*might_sleep*" causes the warning:
  Debug: sleeping function called from invalid context at drivers/base/core.c:343^M
  in_atomic():1, irqs_disabled():0^M
seems likely enough to me.

Perhaps the problem isn't so much a mainline bug in:
  gregkh-driver-allow-sysfs-attribute-files-to-be-pollable.patch 
but rather perhaps this patch has trouble handling this DEBUG warning ??

Recall, as noted before, this crash requires some DEBUG options.

If I disable CONFIG_DEBUG_SPINLOCK and CONFIG_DEBUG_SPINLOCK_SLEEP,
then a build up through and including (and beyond) the following patches:

    cpufreq-_ppc-frequency-change-issues-freq-already-lowered-by-bios.patch
    gregkh-driver-put_device-might_sleep.patch
    gregkh-driver-empty_release_functions_are_broken.patch
    gregkh-driver-allow-sysfs-attribute-files-to-be-pollable.patch

boots fine.  With these two DEBUG options, it crashes during boot
(the "bad" above).

-- 
                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <pj@sgi.com> 1.925.600.0401