Re: kernel panic - not syncing: out of memory and no killableprocesses

From: David Rientjes
Date: Thu Sep 17 2009 - 17:59:20 EST


On Thu, 17 Sep 2009, Eric Paris wrote:

> Absolutely 100% udevd related. It always pops right when udev starts.
> Every time. I don't know how to get that to come out on the serial
> port, you only get to see the kernel messages (although there is nothing
> on the screen other than "Starting udev"
>
> Reverting 3f2aa307c4d26b4ed6509d0a79e8254c9e07e921 causes the problem to
> go away. I now am running a 79b520e87e kernel + your patch (adding
> console_verbose()) + reverting 3f2aa307c4d2 and it seems to be working.
>

Isolating udevd down to an interactivity scheduling change isn't _that_
bizarre. I think the setting of UDEVD_PRIORITY is already mostly
arbitrary anyway and it'll allow 192 children on your 512M machine by
default unless you changed UDEVD_MAX_CHILDS for uid 0.

The default timeout for idle workers is 3 seconds, which may just happen
to be long enough to panic your machine because of low memory. If that's
the case, I don't believe that it's a scheduler issue but rather a root
abuse of setting all udevd threads to be OOM_DISABLE.

What is your udevd --version? The latest is udev-146 released last month.

Maybe linux-hotplug (added to cc) already knows about this issue?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/