error code with ASC/ASCQ 4/1 (``Logical unit is in the process of
becoming ready'') non-fatal. Retry the operation until it will
eventually either yield a real error condition, or finally succeed.
Devices like CD changers or tape drives with a freshly inserted
cartridge should benefit from this.
Should go into 2.2 after some testing in -current. I'd like to see
this in the release if possible.