Re: rules: avoid traversing parent of every single device?

[Alan Jenkins <alan-jenkins@tuffmail.co.uk>]

Kay Sievers wrote:
> On Fri, May 22, 2009 at 16:15, Alan Jenkins <alan-jenkins@tuffmail.co.uk> wrote:
>   
>> I've been looking at what is responsible for all the path lookup activity in
>> coldplug.  On my debian stable system, it looks like every device gets its
>> parent looked up in sysfs.  I think this is due to SUBSYSTEMS matches.
>>
>> I see the udev default rules are different, but it looks like they still
>> test for SUBSYSTEMS on every single device:
>>
>> SUBSYSTEMS="scsi", ATTRS{type}="1|8", GROUP="tape"
>> SUBSYSTEMS="scsi", ATTRS{type}="4|5", GROUP="cdrom"
>> SUBSYSTEMS="scsi", ATTRS{type}="0", GROUP="disk"
>>
>>
>> Should we add SUBSYSTEM="scsi_generic" to these three rules?
>>     
>
> Sounds good. I think the "tape" will need a match for the actual
> scsi-tape devices too? The real "cdrom" and "disk" devices seems
> covered by explicit rules.
>   

Yes, good catch.