No DISK devices reported on systems with SCSI controllers

[Brendan Donegan]

Revision 1091 broke the ability of udev_resource to correctly detect DISK category devices attached to some servers, as evidenced by this console output:

brendan-donegan@nickel:~$ ssh ubuntu@10.189.90.14
Welcome to Ubuntu precise (development branch) (GNU/Linux 3.2.0-17-generic x86_64)

 * Documentation: https://help.ubuntu.com/
Last login: Fri Feb 24 06:35:31 2012 from 10.189.90.1
ubuntu@ubuntu:~$ ls
trunk_1090 trunk_1091
ubuntu@ubuntu:~$ PYTHONPATH=trunk_1091/:$PYTHONPATH trunk_1091/scripts/udev_resource | grep DISK
ubuntu@ubuntu:~$ PYTHONPATH=trunk_1090/:$PYTHONPATH trunk_1090/scripts/udev_resource | grep DISK
category: DISK
category: DISK
category: DISK
product: VIRTUAL DISK
ubuntu@ubuntu:~$

As you can see using the previous revision we get several DISK devices reported. This allows jobs to be successfully generated for tests in jobs/disk.txt.in.

An attempt was made to modify the job to use the 'SCSI' and 'IDE' categories, but the expected information regarding the path to the device in /sys/ is not included in the udev_resource output so it didn't do any good.

Further investigation is needed to find the common trait of systems that exhibit this problem.

[Brendan Donegan (brendan-donegan)]

It's worth pointing out that the broken output is much shorter than the working one. This seems suggest devices are being discarded.

[Brendan Donegan (brendan-donegan)]

On systems with SCSI disk controllers, udev_resource was not picking up DISK category devices because it was discarding them due to the fact they had no 'product' field. This was because when determining what constituted a valid DISK device only the 'ata' ID_BUS value was used.