lkml.org 
[lkml]   [2010]   [Dec]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] avoid race condition in pick_next_task_fair in kernel/sched_fair.c
    On Tue, Jun 29, 2010 at 12:43:35PM +0200, Peter Zijlstra <peterz@infradead.org> wrote:
    > On Tue, 2010-06-29 at 15:10 +0800, shenghui wrote:
    > > I think some lock on the metadata can fix this issue, but we may
    > > change plenty of code to add support for lock. I think the easist
    > > way is just substacting nr_running before dequing tasks.
    >
    > But all that is fully serialized by the rq->lock.. so I'm really not
    > seeing how this can happen.

    Hi,

    Here is a panic I got today:

    http://frugalware.org/~vmiklos/pics/bug/2.6.37-rc6.png

    More details:

    I get this sometimes on boot or shutdown when testing systemd. I did not
    get it with sysvinit, so I guess it may be related to systemd's heavy
    cgroups usage, but I'm not sure. Sadly it isn't 100% reproducible but I
    usually hit it at least once a day.

    The config is here:
    http://frugalware.org/~vmiklos/logs/2.6.37-rc6.config (I just did a
    yes "" | make config to update it to 2.6.37-rc6.)

    I got something similar with 2.6.36.1 as well:

    http://frugalware.org/~vmiklos/pics/bug/2.6.36.1.png

    Ah, and this is on i686 in VMware - though given that I never had this
    problem with systemd, I guess it won't be an emulator bug. :)

    I'm not familiar with the sched code, is it possible that this is
    related?

    Thanks,

    Miklos
    [unhandled content-type:application/pgp-signature]
    \
     
     \ /
      Last update: 2010-12-19 03:23    [W:0.075 / U:0.108 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site