[08:59] apw: Hi. I got kernel panic again. Where should i paste photos? [09:01] UNIm95, file a bug, and add them to that bug: use 'ubuntu-bug linux' to make the bug [09:01] apw: what is ubuntu-bug linux? Console program? Website? [09:01] something to run in a terminal yes [09:17] apw: Damn. I got Launchpad error =) [09:20] apw: I have submitted this. What should i do next? Wait? [09:28] UNIm95, let us know the LP# here for one [09:31] apw: What do you mean with LP#? if you mean bug number under launchpad it is #1497184. Link here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1497184 [09:31] Ubuntu bug 1497184 in linux (Ubuntu) "Kernel-panic with 3.13-64 generic kernel" [Undecided,Confirmed] [09:31] yep that [09:34] henrix, ^ looks like a regression in trusty-proposed kernel ... [09:34] UNIm95, does that trace seem consistent in your failures ? [09:35] UNIm95, particuarly is that "BUG: ..../skbuff.c:1290" part appear in other ones [09:36] apw: Not sure. Now I'm still using *-64- kernel and wait for another panic. When it happens i post more photos. [09:36] UNIm95, thanks that is exactly what we need, you are not the only person "feeling" there is an issue in here [09:37] UNIm95, and thanks for 1) testing -proposed and 2) reporting the issues to us [09:38] apw: Please. I is not a problem for me. I have backups =) [09:38] heh, thanks === apw is now known as apw_ === apw_ is now known as cafetiere === cafetiere is now known as apw [09:47] * smb feels a disturbance in the coffee namespace [09:55] smb: ok, i *may* have found something related with this bug. if your bored, here's what i found: [09:55] smb: trysty -64 kernel includes commit 738ac1ebb96d ("net: Clone skb before setting peeked flag") [09:55] that sounds suspicious indeed [09:56] smb: however, there's an upstream commit (not included in trusty yet): a0a2a6602496 ("net: Fix skb_set_peeked use-after-free bug") [09:56] which fixes the other one [09:56] nnng [09:56] henrix, yeah. I am currently trying to cause it to crash with -64 in a VM. If that succeeds I can have a look with that added [09:57] smb: cool, thanks [09:57] henrix, but use-after-free sounds a lot like what may happen [09:58] smb: yeah, the only thing is that none of these functions actually show up in the kernel trace. but since the kernel is tainted, it could have happen before [09:58] *don't show [09:58] henrix, absolutely. the pain with use-after-free [10:03] smb: btw, if the issue you're hitting is really due to this commit, it seems to be related with broadcast/multicast ;-) [10:03] (according to the commit msg) [10:04] henrix, hmmm... so the method to trigger it is actually the dhcp client running... likely... [11:17] smb: build on-going in gloin:/tmp/kernel-henrix-RVtd9xTj [12:39] UNIm95: i've commented on the bug with a link to a test kernel [12:39] UNIm95: The comment points to the possible issue (and the fix) [12:39] henrix: ok. [12:40] UNIm95, how long did it take to reproduce in general ? [12:40] apw: smb: btw, looks like this also impacs vivid [12:42] apw: At home laptop worked for 4 hours, than sleep for 8 hours and, finally, after 2 hours word panic. [12:42] work* [12:44] apw: one time a got this after ~30min uptime [12:45] henrix, gah [12:45] henrix: i will try this kernel a later. I need to do my work [12:45] henrix, i've nom'd it to those two for now [12:46] henrix: i have downloaded this kernel [12:46] UNIm95, let us know how you get on [12:46] Sure [12:46] UNIm95: ack, thanks! [12:46] but i am suspicious this is the issue and fix [12:49] henrix: the only question: "and introduces a use-after-free bug, fixed with upstream commit" [12:49] It means than this bug appers with high memory load? [12:50] UNIm95: from these commits description it should occur in the broadcast and multicast packages receive paths, so not really a memory stress issue [12:51] s/packages/packets [12:51] henrix: network packets? [12:52] UNIm95: yep [12:52] should i emulate DDOS? [12:52] on my own laptop? [12:53] Or is possible to make some thing like this. [12:53] UNIm95, it is predicted taht dhcpclient would tickle the bug [12:53] UNIm95, so setting your dhcp refresh time on your router to 5m might make it a lot more likley to occur [12:53] lots of packets not so likley to trigger it, as tehy are normally unicast [12:55] apw: and doesn't matter Wlan or ethernet? [12:55] i don't believe so from the description [12:55] henrix, ^ [12:57] apw: i... don't think so either, it's in the core network code. anyway, looking at UNIm95 photos, it seems to have occurred while using ethernet (e1000e) [12:57] good point [12:57] but again, i believe that's irrelevant -- if this is the issue, it's in the core code, so it doesn't matter [12:58] henrix: apw yesterday at home i used wlan and got only kernel oops that was catched with apport-gtk. [12:59] do you have access to ubuntu's apport infrastructure? [12:59] UNIm95, the symptoms of this would be pretty random, as it is a use after free which could literally break anything [12:59] UNIm95, we may be able to find it yes [13:00] look for toshiba tecra laptop a11 [13:01] It was at evening. 20:00 apw, henrix, so far not been able to hit it in a more artificial environment but I guess its random by nature [13:43] tjaalton, hey are you fixing this initramfs-tools thing for the firmware ... i was about to, but i see you ahve it assigned [13:44] apw: that's when it was a kernel bug, you can have it :) [13:44] tjaalton, ack [13:44] thanks [14:42] cking_: hello, it's me again :) [14:42] Just was going to disable the memory threshold for NM health check but noticed that it's been passing for a few days. [14:42] *memory threshold tests [14:42] https://jenkins.qa.ubuntu.com/view/Trusty/view/Smoke%20Testing/job/trusty-desktop-i386-smoke-health-check/ [14:43] so i'm wondering if that's OK to let that run for a few more days to see if this has really settled [14:43] psivaa, ok, lets see how it runs over the next few days [14:43] cking_: ack, thanks === hggdh is now known as hggdh_ === hggdh_ is now known as hggdh__ === hggdh__ is now known as hggdh [15:47] hey all, is anyone around that could help me with a cpuacct cgroup question/issue/bug? [17:20] t3hSteve, it is eod for me, but it is just best to ask the question and see who responds [17:22] ok, so basically I notice that on (at least up to) 3.13.0-64, the cpu usage reported in cpuacct.stat is significantly lower than the actual CPU usage as reported by say, top or /proc//stat [17:25] this is on ubuntu 12.04, I seem to recall on 14.04 it was correct, but oddly enough I think it was on the same kernel version [17:40] t3hSteve, hrm, that sounds odd if the kernle version is the same [17:40] yeah, its very odd =/ [17:40] looking around bug trackers I cant see any reference to anything like this [17:41] but its a significant under-reporting from the cgroup [17:41] t3hSteve, sounds like some repeatable test is required, if you could file a bug against the kernel "ubuntu-bug linux", and could detail the two platforms that produce different numbers, and how to get the numbers [17:41] ex top reports 120% and the cgroup reports .9 [17:41] t3hSteve, then someone might be able to repro it [17:41] I can do that [17:41] althought we'll see how easy it is to reproduce :P [17:42] t3hSteve, heh .. i know ... things like this normaly go away when you try and make them reproducible [17:43] :P [17:43] the full context is we're running mesos in AWS [17:43] t3hSteve, drop the LP#number in here when you have done so, so we can find it [17:43] and the numbers I get out of mesos (which just reads the cgroup) are way different from what I see on the machine itself (top, /proc, etc) [18:34] henrix: apw damn. without kernel change i have 10 hours uptime without panic. [19:59] so re: my cgroup issue, it looks like the more threads a process has the more the cpuacct.stats numbers diverge [20:36] apw: https://bugs.launchpad.net/ubuntu/+source/linux-lts-raring/+bug/1497447 [20:36] Ubuntu bug 1497447 in linux-lts-raring (Ubuntu) "cgroup cpuacct.stats underreports cpu usage" [Undecided,New] [20:36] I'm not sure if I filed it against the right package? [20:43] Hi all, I think the "flo" branch needs to be patched to support newer Nexus 7 devices with an updated eMMC controller, I need to compile a new kernel and patch my boot.img and recovery.img in order to get Ubuntu Touch to install on my Nexus 7 [20:43] details are here: https://github.com/ddagunts/UTCWM_N7_patch [21:41] old_benz, if you could file a bug against linux-flo with that information and drop the bug # in here ... [22:27] apw: will do, need to make an account