Re: frequent lockups in 3.18rc4

From: Ingo Molnar
Date: Sat Dec 13 2014 - 03:28:00 EST



* Ingo Molnar <mingo@xxxxxxxxxx> wrote:

>
> * Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> > On Fri, Dec 12, 2014 at 10:54 AM, Dave Jones <davej@xxxxxxxxxx> wrote:
> >
> > >
> > > Something that's still making me wonder if it's some kind of
> > > hardware problem is the non-deterministic nature of this bug.
> >
> > I'd expect it to be a race condition, though. Which can easily
> > cause these kinds of issues, and the timing will be pretty
> > random even if the load is very regular.
> >
> > And we know that the scheduler has an integer overflow under
> > Sasha's loads, although I didn't hear anything from Ingo and
> > friends about it. Ingo/Peter, you were cc'd on that report,
> > where at least one of the multiplcations in wake_affine() ended
> > up overflowing..
>
> Just to make sure, is there any other wake_affine report other
> than the one in this thread? (I tried a wake_affine full text
> search on my inbox and didn't find anything that appeared
> relevant.)

Found the report from Sasha:

sched: odd values for effective load calculations

right?

Thanks,

Ingo
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