Re: Crashes with 874bbfe600a6 in 3.18.25

On Wed, 3 Feb 2016, Tejun Heo wrote:

On Wed, Feb 03, 2016 at 07:46:11PM +0100, Thomas Gleixner wrote:

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So I think 874bbfe600a6 is really bogus. It should be reverted. We
already have a proper fix for vmstat 176bed1de5bf ("vmstat: explicitly
schedule per-cpu work on the CPU we need it to run on"). This which
should be used for the stable trees as a replacement.

It's not bogus.  We can't flip a property that has been guaranteed
without any provision for verification.  Why do you think vmstat blow
up in the first place?  vmstat would be the canary case as it runs
frequently on all systems.  It's exactly the sign that we can't break
this guarantee willy-nilly.

You're in complete failure denial mode once again.

Well, you're in an unnecessary escalation mode as usual.  Was the
attitude really necessary?  Chill out and read the thread again.
Michal is saying the dwork->cpu assignment was bogus and I was
refuting that.

Right, but at the same time you could have admitted, that the current state is
buggy and needs a sanity check in unbound_pwq_by_node().
 

Michal brought it up here but there's a different thread where Mike
reported NUMA_NO_NODE issue and I already posted the fix.

 http://lkml.kernel.org/g/20160203185425.GK14091@mtj.duckdns.org

5 minute ago w/o cc'ing the people who participated in that discussion.

Thanks,

	tglx