panic in destroy_devl: null si_devsw

[Bruce M. Simpson]

Andriy Gapon wrote:
> ...
> About the code that called destroy_dev(): it created cdev probably too
> early, failed to allocate some system resource, so it went to destroy
> the newly created cdev. Non-null cdevsw was definitely provided to make_dev.
>
>   

I saw a very, very similar panic with 7.1 sources and jhb's ppc locking 
patch yesterday.

Could this be related to a difference in unit numbers between 8.x and 8.x?