Re: Regression with a0747a859ef6 ("bdi: add error handle for bdi_debug_register")

[Bruno Wolff III]

On Fri, Dec 15, 2017 at 10:04:32 +0800,
 weiping zhang <zwp10758@xxxxxxxxx> wrote:
> I just want to know WARN_ON WHAT in device_add_disk,
> if bdi_register_owner return error code, it may fail at any step of following:

Was that output in the original boot log? I didn't see anything there 
that had the string WARN_ON. The first log was from a Fedora kernel. The 
second from a kernel I built. I used a Fedora config though. The config 
was probably from one of their nodebug kernels, I could build another 
one using a config from a debug kernel. Would that likely provide what 
you are looking for?