[16:19] <vlad_starkov> I probably found a bug in some module. Can't boot Ubuntu Server on my machine. It raises CPU soft lockup errors all the time. The system even can't boot. 
[16:22] <vlad_starkov> I tried to boot from grml USB flash, and it does almost all the same. But when I tried to boot grml with 'noudev' boot option, the grml has booted just fine and htop shows me all my 8 CPU cores with 0-2% load.
[16:22] <vlad_starkov> What does 'noudev' boot option in my case?
[16:24] <brendand> does anyone know about low-power states used in the phablet image? is there any sort of shifting of power states - say when the screen off button is pressed?
[16:29] <BenC> apw: How goes the integration?
[16:30] <apw> BenC, looking good according to the testing we have done, working on the 'final' version right now as it happens
[16:31] <BenC> apw: Is it in git?
[16:31] <apw> BenC, shortly ...
[16:31] <BenC> I'd like to test out the ppc bits
[16:31] <BenC> apw: I'm hoping no changes were made to the configs :)
[16:31] <apw> i'll ping you when i've pushed it ... configs are identicle indeed
[16:31] <BenC> Thanks for that
[16:39] <vlad_starkov> Question: Given I can't boot Ubuntu Server 12.04. It always raises CPU soft lockup error. What would be the right strategy to find the buggy module and disable it?
[16:43] <smb> The softlockup warnings should have a stack-trace that should hint what is waiting. That might indicate which area or even module is involved
[17:18] <vlad_starkov> smb: so I have to wait while such information will appear on screen or should I apply some special 'verbose'-like boot option to get it?
[17:21] <vlad_starkov> smb: the CPU lockups begins after 'Running /scripts/init-bottom ... done' and 'init: ureadahead main process (369) terminated with status 5'
[17:22] <vlad_starkov> smb: then it continues with "BUG: soft lockup – CPU#0 stuck for 30s! [modprobe:476]"
[17:22] <vlad_starkov> smb: then the same with "... [flush-8:0:557]"
[18:51] <apw> BenC, on master-next let me know if it works ok :)
[18:52] <BenC> apw: I'll test it tonight, thanks. 
[19:37] <apw> BenC, great thanks
[20:07] <vlad_starkov> BUG detected http://paste.ubuntu.com/6828163/
[20:07] <smoser> [  588.212384] perf samples too long (2512 > 2500), lowering kernel.perf_event_max_sample_rate to 50000
[20:07] <smoser> [ 8632.343242] perf samples too long (5010 > 5000), lowering kernel.perf_event_max_sample_rate to 25000
[20:08] <smoser> what does the above mean ? I'm seeing it on trusty, on non-ssd laptop.
[20:35] <mwhudson> smoser: the way perf works iiuc is that there is a ring buffer that the kernel shoves data into and the user space process reads it out and writes it to disk
[20:35] <mwhudson> i think that message means the user space process isn't keeping up