Re: Oops on Power8 (was Re: [PATCH v2 1/7] workqueue: make workqueue available early during boot)

On Mon, Oct 10, 2016 at 09:02:53AM -0400, Tejun Heo wrote:

Hello, Michael.

On Mon, Oct 10, 2016 at 09:22:55PM +1100, Michael Ellerman wrote:

quoted

This patch seems to be causing one of my Power8 boxes not to boot.

Specifically commit 3347fa092821 ("workqueue: make workqueue available
early during boot") in linux-next.

If I revert this on top of next-20161005 then the machine boots again.

I've attached the oops below. It looks like the cfs_rq of p->se is NULL?

Hah, weird that it's arch dependent, or maybe it's just different
config options.  Most likely, it's caused by workqueue_init() call
being moved too early.  Can you please try the following patch and see
whether the problem goes away?

And if it does, can you please post the boot log with kernel boot
option "initcall_debug=1" specified?

Thanks.

-- 
tejun