Re: "Unkillable processes" and INFO: task ... blocked for more than 120 seconds

From: Manuel Reimer
Date: Fri Feb 20 2015 - 12:30:45 EST


Hello,

I can add that this problem seems to be reproducible for me so either some change in one of the latest kernel updates caused this or something on my system hardware is starting to fail...

If I open "a few" photos on GIMP (enough to get the application memory usage above 40%) then I'm able to close GIMP without any problems but it seems to get stuck in exactly the same way as it happened the first time.

My system kernel: Linux manuelspc 3.18.6-1-ARCH #1 SMP PREEMPT Sat Feb 7 08:44:05 CET 2015 x86_64 GNU/Linux


On 02/20/2015 06:13 PM, Manuel Reimer wrote:
Hello,

today, I had the following problem:

I was editing a few photos in GIMP and after I finished with that, I
tried to close GIMP which failed. KDE offered me to terminate the
application which also didn't work.

So I opened a terminal and tried "killall -9 gimp" --> No success

Next I tried "pgrep gimp" to get the PID of the hanging process. With
the result that pgrep now also got stuck with hangup of my whole shell.

A "strace pgrep gimp" told me that pgrep actually hung up on a read on
"/proc/18294/cmdline" so I guessed that this could be my hanging GIMP
process. But even "kill -9 18294" was not able to kill the process.

So I switched over to a VT shell and logged in as root which at first
hung up the login shell, but was fixable by pressing "Ctrl + C". Even as
root I was unable to kill GIMP.

The kernel didn't actually crash. My music player continued to play
nicely and my mail client was fully usable.

I saved some log output to pastebin: http://pastebin.com/FPDvyePJ

What has been happening here? Why is it possible that I actually get
non-killable processes?

If you need additional information, please ask.

Thank you very much in advance.

Manuel



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