Re: [RFC] [PATCH] Loaded driver modalias

[Nathaniel McCallum <nathaniel@natemccallum.com>]

Kay Sievers wrote:
> On Tue, Nov 4, 2008 at 19:39, Nathaniel McCallum
> <nathaniel@natemccallum.com> wrote:
>   
>> Please CC me to responses as I'm not subscribed to LKML.  Also, this is my
>> first kernel patch, advise is certainly welcome.
>>
>> For something I'm working on I have the need to answer the question, "given
>> a hardware ID, does Linux distro X have a driver to support this hardware?"
>> and more specifically, "which drivers support this hardware?" I can,
>> generally speaking, get this data from files like
>> /lib/modules/*/modules.alias.  However, this does not work for drivers built
>> into the kernel.  With that in mind, I've cooked up a little proof of
>> concept. Basically, its a sysfs file
>> /sys/modules/$module/drivers/$driver/modalias that, when read, contains
>> modalias-style filters for this driver.
>>
>> The attached patch only does this for PCI drivers, each subsystem would need
>> a patch like this.  Is this idea crazy?  Is there a better implementation?
>>     
>
> Hmm, what if that gets larger than 4k? It seems not really like
> something for sysfs. There are also drivers which export a modalias
> which matches more devices, than the device it actually would accept
> to bind to. Some driver have logic in the match() function to exclude
> stuff.
>   
Also, would it not be possible to break the 4k barrier with a binary 
attribute?

Nathaniel