udev and ISA network cards

udev and ISA network cards

[Olaf]

Hi,


I would like to use ISA cards in combination with persistent net rules, 
especially renaming ethX to something like internal / internet / etc. as 
this is somewhat easier to remember ;-)

Is this at all possible?
Or is this more a case of: will never work 'cause the drivers are not 
cooperating enough?
Or even isapnp missing (this box is not playing along with pnp)?

I have cards with 3c509 and ne driver. Both cards do work, apart from 
the persistent net stuff :-/
Monitoring using udevadm monitor shows udevd is at least doing 
'something' (see snippet below) but it is either ignoring ISA or the 
kernel/driver is missing some information. udevadm info provides very 
little information:
# udevadm info --query all --path=/sys/bus/isa/drivers/3c509/3c509.0 
--attribute-walk

  looking at device '/devices/isa/3c509.0':
    KERNEL="3c509.0"
    SUBSYSTEM="isa"
    DRIVER="3c509"

  looking at parent device '/devices/isa':
    KERNELS="isa"
    SUBSYSTEMS=""
    DRIVERS=""


Please advise.
Thanks.

Olaf


KERNEL[1246007462.702266] add      /module/3c509 (module)
UDEV  [1246007462.704344] add      /module/3c509 (module)
KERNEL[1246007462.706222] add      /bus/pnp/drivers/3c509 (drivers)
KERNEL[1246007462.709164] add      /bus/isa/drivers/3c509 (drivers)
KERNEL[1246007462.711276] add      /devices/isa/3c509.0 (isa)
KERNEL[1246007462.713145] add      /devices/virtual/net/eth0 (net)
KERNEL[1246007462.715007] add      /devices/isa/3c509.1 (isa)
KERNEL[1246007462.720220] remove   /devices/isa/3c509.1 (isa)
KERNEL[1246007462.721475] add      /devices/isa/3c509.2 (isa)
KERNEL[1246007462.722471] remove   /devices/isa/3c509.2 (isa)
KERNEL[1246007462.726667] add      /devices/isa/3c509.3 (isa)
UDEV  [1246007462.728006] add      /bus/pnp/drivers/3c509 (drivers)
KERNEL[1246007462.729041] remove   /devices/isa/3c509.3 (isa)
KERNEL[1246007462.730033] add      /devices/isa/3c509.4 (isa)
KERNEL[1246007462.731688] remove   /devices/isa/3c509.4 (isa)
KERNEL[1246007462.736603] add      /devices/isa/3c509.5 (isa)
KERNEL[1246007462.737985] remove   /devices/isa/3c509.5 (isa)
KERNEL[1246007462.739210] add      /devices/isa/3c509.6 (isa)
KERNEL[1246007462.743217] remove   /devices/isa/3c509.6 (isa)
UDEV  [1246007462.744583] add      /bus/isa/drivers/3c509 (drivers)
KERNEL[1246007462.745817] add      /devices/isa/3c509.7 (isa)
KERNEL[1246007462.747043] remove   /devices/isa/3c509.7 (isa)
KERNEL[1246007462.752101] add      /bus/eisa/drivers/3c579 (drivers)
UDEV  [1246007462.756301] add      /devices/isa/3c509.0 (isa)
UDEV  [1246007462.765593] add      /devices/virtual/net/eth0 (net)
UDEV  [1246007462.780655] add      /devices/isa/3c509.1 (isa)
UDEV  [1246007462.788468] remove   /devices/isa/3c509.1 (isa)
UDEV  [1246007462.796445] add      /devices/isa/3c509.2 (isa)
UDEV  [1246007462.804252] remove   /devices/isa/3c509.2 (isa)
UDEV  [1246007462.812270] add      /devices/isa/3c509.3 (isa)
UDEV  [1246007462.819985] remove   /devices/isa/3c509.3 (isa)
UDEV  [1246007462.827933] add      /devices/isa/3c509.4 (isa)
UDEV  [1246007462.835793] remove   /devices/isa/3c509.4 (isa)
UDEV  [1246007462.843736] add      /devices/isa/3c509.5 (isa)
UDEV  [1246007462.851621] remove   /devices/isa/3c509.5 (isa)
UDEV  [1246007462.859457] add      /devices/isa/3c509.6 (isa)
UDEV  [1246007462.867219] remove   /devices/isa/3c509.6 (isa)
UDEV  [1246007462.875175] add      /devices/isa/3c509.7 (isa)
UDEV  [1246007462.883008] remove   /devices/isa/3c509.7 (isa)
UDEV  [1246007462.890990] add      /bus/eisa/drivers/3c579 (drivers)

Re: udev and ISA network cards

[Kay Sievers]

On Fri, Jun 26, 2009 at 12:42, Olaf<mailinglists@ban-solms.de> wrote:
> I would like to use ISA cards in combination with persistent net rules,
> especially renaming ethX to something like internal / internet / etc. as
> this is somewhat easier to remember ;-)
>
> Is this at all possible?

It should work.

> KERNEL[1246007462.711276] add      /devices/isa/3c509.0 (isa)

This is the card device.

> KERNEL[1246007462.713145] add      /devices/virtual/net/eth0 (net)

This is the network interface device, which needs to be connected to
the card device as a parent.

Then it would look like:
        /devices/isa/3c509.0/net/eth0

and only then the persistent rule generator will kick in.

This needs to be fixed in the kernel driver, it needs to set the
parent device of the netdev before it is registered.

Kay

Re: udev and ISA network cards

[Olaf]

Kay Sievers wrote:

>> I would like to use ISA cards in combination with persistent net rules,
>> especially renaming ethX to something like internal / internet / etc. as
>> this is somewhat easier to remember ;-)
>>
>> Is this at all possible?
> 
> It should work.

[... snip snip ...]

> This needs to be fixed in the kernel driver, it needs to set the
> parent device of the netdev before it is registered.

I was afraid you were going to say something like that ...
Ah well, I'll start staring at kernel driver code then.


regards

Olaf


PS: I'd appreciate any hints, pushes, shoves etc. to get me in proper 
direction.

Re: udev and ISA network cards

[Hannes Reinecke]

Hi Olaf,

Olaf wrote:
> Kay Sievers wrote:
> 
>>> I would like to use ISA cards in combination with persistent net rules,
>>> especially renaming ethX to something like internal / internet / etc. as
>>> this is somewhat easier to remember ;-)
>>>
>>> Is this at all possible?
>>
>> It should work.
> 
> [... snip snip ...]
> 
>> This needs to be fixed in the kernel driver, it needs to set the
>> parent device of the netdev before it is registered.
> 
> I was afraid you were going to say something like that ...
> Ah well, I'll start staring at kernel driver code then.
> 
Which would help you only to a very limited amount.

udev relies on device autodetection, ie a (hardware) device must
have some means by which someone else can identify it.
With PCI this is no problem at all, as each device has its
vendor/device ID as per spec.

ISA OTOH is a different beast. And if you trawl memory back to
the ISA days, the main problem with it was that it _doesn't_
have an independent identifier.
IIRC you couldn't even identify the slot itself; each device
mostly hardcoded to use a specific I/O address / region and
some IRQ. And it was up to the task of the admin to ensure
each device got a separate addr/irq tuple.

Hence they invented PnP IDs which provide for exactly this
sort of identifier.

So, translated to udev this means that any ISA card providing
PnP IDs should work, or at least it should be possible to make
it work with udev.
Any ISA card _not_ providing PnP IDs you're basically out of luck.
The only choice you'd have here is to use some sort of lookup-table
which provides a static assignment between IO addresses and drivers.

HTH.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		      zSeries & Storage
hare@suse.de			      +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: Markus Rex, HRB 16746 (AG Nürnberg)

Re: udev and ISA network cards

[Olaf]

Hi Hannes,


thanks for your thoughts!

> udev relies on device autodetection, ie a (hardware) device must
> have some means by which someone else can identify it.
> With PCI this is no problem at all, as each device has its
> vendor/device ID as per spec.
> 
> ISA OTOH is a different beast. And if you trawl memory back to
> the ISA days, the main problem with it was that it _doesn't_
> have an independent identifier.
> IIRC you couldn't even identify the slot itself; each device
> mostly hardcoded to use a specific I/O address / region and
> some IRQ. And it was up to the task of the admin to ensure
> each device got a separate addr/irq tuple.


For ISA (and PCI, USB, etc.) I use an additional method and do not fully 
rely on autodetection to work.

In my case I have some sort of network configuration file, which 
includes kernel modules, option if so required (i.e. ISA port addresses, 
IRQs etc.) and the things needed for if up.
My network init script uses this config file to modprobe first and then 
configure each interface.


> Hence they invented PnP IDs which provide for exactly this
> sort of identifier.
> 
> So, translated to udev this means that any ISA card providing
> PnP IDs should work, or at least it should be possible to make
> it work with udev.
> Any ISA card _not_ providing PnP IDs you're basically out of luck.
> The only choice you'd have here is to use some sort of lookup-table
> which provides a static assignment between IO addresses and drivers.

The only problem I face is the lack of autodetection, so the config file 
needs to be filled more or less manually. But there is not much one can 
do about that with ISA cards.


OK, I have one additional problem, and that is the udev net device 
renaming which is (understandably) not working with ISA cards ;-)


thanks

Olaf