Re: [wireless] wireless: Keep phy name consistent across module reloads.

[Ben Greear <greearb@candelatech.com>]

On 09/24/2010 02:18 PM, Johannes Berg wrote:
> On Fri, 2010-09-24 at 14:10 -0700, Ben Greear wrote:
>
>>> We cannot do this because otherwise operations you attempt to do one one
>>> PHY will race with re-creating of the same phy index. For the same
>>> reason, interface indexes aren't reused for netdevs.
>>>
>>> If this bothers you so much, you can easily write a udev rule that
>>> renames all your phys to "myphy" or whatever.
>>
>> Sorry about that.
>>
>> Would a similar patch be acceptable that just set the name to the first
>> available phyX, but left the index to increment monotomically as it does
>> now be OK?
>
> Actually, right now it doesn't even allow you to use a "phy%d" name,
> which is because I don't want (sysfs, debugfs) errors coming from doing
> "iw phy0 set name phy1" and then plugging in a new device ... In doing
> that, I manage to avoid having to allocate two different numbers...

I tried rename few months ago, to rename back to phy0, and it failed
for no obvious reason..so I just assumed rename didn't work at all.
Would you like a patch to print something in kernel logs when someone
tries to rename to phy%d?

> I suppose it'd be possible to treat this more like interfaces. Want to
> also make it per net namespace? ;-)

Probably best for all involved if I don't mess with namespaces right now,
but I'll be happy to work on (or test) a patch to find the first un-used phyX name,
if that's what you mean.

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com