Messages in this thread | | | Date | Sun, 23 Mar 2014 16:14:31 +0100 (CET) | From | Thomas Gleixner <> | Subject | Re: rb tree hrtimer lockup bug (found by perf_fuzzer) |
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On Sat, 22 Mar 2014, Thomas Gleixner wrote:
> On Sat, 22 Mar 2014, Thomas Gleixner wrote: > > On Fri, 21 Mar 2014, Vince Weaver wrote: > > > > > On Fri, 21 Mar 2014, Thomas Gleixner wrote: > > > > > > > > I'm a complete idiot. I was staring at oaddr and did not notice that > > > > descr->name is the real culprit. Sorry. Delta patch below. > > > > > > OK. The log was much longer this time, attached. > > > > Hmmm. > > > > [ 2.739858] NULL pointer dereference at (null) > > [ 2.747390] IP: [< (null)>] (null) > > [ 2.752970] PGD 0 > > [ 2.755287] Oops: 0010 [#1] SMP > > > > So this time the CPU branched to NULL. So let me recap. > > > > First you had the explosion in the hrtimer code. After enabling debug > > stuff it went to the timer_list and now it looks different again. > > > > So that looks more like a random memory corruption. > > > > Nasty to debug. And of course it does not reproduce here. I'll throw > > your config at more machines in the hope that something will trigger > > it. > > I've refined the trace_printk stuff in the hope to get a bit more info > out of it.
You might also try with the trace_printks removed. That wont give us the history, but maybe then the bug happens again at some decodable place.
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