Re: perf: fuzzer BUG: KASAN: stack-out-of-bounds in __unwind_start

From: Peter Zijlstra
Date: Tue Nov 29 2016 - 07:43:42 EST

On Mon, Nov 28, 2016 at 11:52:41PM -0600, Josh Poimboeuf wrote:

> Did a little digging on git blame and found the following commit (which
> seems to be the cause of the KASAN warning and missing stack dump):
> bc1dce514e9b ("rcu: Don't use NMIs to dump other CPUs' stacks")
> I presume this commit is still needed because of the NMI printk deadlock
> issues which were discussed at Kernel Summit. I guess those issues need
> to be sorted out before the above commit can be reverted.

Also, I most always run with these here patches applied:

People are very busy polishing the turd we call printk, but from where
I'm sitting its terminally and unfixably broken.

I should certainly add a revert of the above commit to the stack of
patches I carry.