Re: frequent softlockups with 3.10rc6.

From: Steven Rostedt
Date: Tue Jun 25 2013 - 13:21:37 EST


On Tue, 2013-06-25 at 12:55 -0400, Dave Jones wrote:

> While I've been spinning wheels trying to reproduce that softlockup bug,
> On another machine I've been refining my list-walk debug patch.
> I added an ugly "ok, the ringbuffer is playing games with lower two bits" special case.
>
> But what the hell is going on here ?
>
> next->prev should be prev (ffff88023c6cdd18), but was 00ffff88023c6cdd. (next=ffff880243288001).
>
> (trace comes from the same ringbuffer code)

What's the above saying? ffff880243288000->prev == 00ffff88023c6cdd but
it should have been ffff88023c6cdd18? That is: ffff88023c6cdd18->next ==
ffff880243288001?

Not sure how that would mess up. The ring-buffer code has lots of
integrity checks to make sure nothing like this breaks.

-- Steve


--
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/