Quadra SCSI problem

[Robert Swindells <rjs%fdy2.demon.co.uk@localhost>]

Is anyone else having problems booting systems that use the esp(4)
driver ? My Q950 just hangs when it should mount the root filesystem.

I can drop into DDB but don't see anything useful in the stack trace.

I presumed at first that I had broken something in my local tree, but
a GENERIC kernel from the daily builds of HEAD has the same problem.

The GENERIC kernel from 5.0 boots fine.

A change went into the driver recently, but the same code is working
fine under sparc & sparc64.

Robert Swindells