Re: 3.2.0-rc4+ (Linus GIT af968e29acd91ebeb4224e899202c46c93171ecd)-- Freezing of tasks failed after 20.01 seconds (1 tasks refusing to freeze, wq_busy=0):

From: Miles Lane
Date: Sat Dec 03 2011 - 12:17:56 EST


On Sat, Dec 3, 2011 at 11:44 AM, Srivatsa S. Bhat
<srivatsa.bhat@xxxxxxxxxxxxxxxxxx> wrote:
> On 12/03/2011 09:07 PM, Miles Lane wrote:
>
>> Thanks!  The patch worked perfectly.
>>
>>         Miles
>>
>
>
> I had written that patch when I found a possibility of freezing failure when
> looking at the code. I hadn't really hit the problem myself. (And to test my
> patch's effectiveness, I had used a synthetic scenario that I had created.)
>
> So, since you seem to have hit the problem during normal usage itself and not
> while doing anything fancy, out of curiosity, what triggered the problem?

I was intentionally checking for problems with reading the contents of
the /sys and /proc trees. So I ran:
find /sys -name "[a-z]*" | xargs head
and
find /proc -name "[q-z]*" | xargs head
and then, while the commands were processing files I suspended
(unsuccessfully) the laptop.

I have often found bugs in this area, so I periodically run this test.
Sometimes it turns up problems in accessing specific information in
the data files. This is the first time I added trying to suspend
while the test was running.

Happy coding!
Miles
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