On Wed, Aug 23, 2017 at 05:12:16AM +1000, Stephen Rothwell wrote:

Hi Paul,

On Tue, 22 Aug 2017 11:59:23 -0700 "Paul E. McKenney" [off-list ref] wrote:

quoted

On Wed, Aug 23, 2017 at 04:14:24AM +1000, Stephen Rothwell wrote:

quoted

Hi all,

On Wed, 23 Aug 2017 04:11:17 +1000 Stephen Rothwell [off-list ref] wrote:  

quoted

This tree fails to boot on my qemu test.  2 boot logs attached.

Paul, Nick, is this the same/similar to the other RCU/lockup bug you
are chasing.  This is the first time I have seen this failure.

This qemu boot is in full emulation mode if I add --enable-kvm to the
qemu command, it does not fail to boot.  (the test just boots and then shuts down)  

Boot logs attached this time.  

That does not look good!

Given that the hard lockup happened during timer lock acquisition, I
have to ask if you built with lockdep...

$ grep LOCKDEP .config
CONFIG_LOCKDEP_SUPPORT=y

so, no.  This is just a powerpc pseries_le_defconfig build.

This is without Nick's recent patch, I am guessing?

Hmmm...  My testing of that patch omitted lockdep as well.  Rerunning
on the full set of rcutorture scenarios...

							Thanx, Paul