linux-kernel - Re: "permanently" unbind a device from a driver?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <d82e647a0901210744t1655bacesf23bcd54e30002e9@mail.gmail.com>
Date:	Wed, 21 Jan 2009 23:44:03 +0800
From:	Ming Lei <tom.leiming@...il.com>
To:	Greg KH <greg@...ah.com>
Cc:	Michael Tokarev <mjt@....msk.ru>,
	Linux-kernel <linux-kernel@...r.kernel.org>,
	Linux USB list <linux-usb@...r.kernel.org>
Subject: Re: "permanently" unbind a device from a driver?

2009/1/21 Greg KH <greg@...ah.com>:
> On Tue, Jan 20, 2009 at 11:50:07PM +0300, Michael Tokarev wrote:
>> Is there a way to stop a module from claiming a
>> given device no matter how/when it gets plugged?
>>
>> For example, there's a series of power supplies
>> (UPSes) with USB connection (common nowadays)
>> which, by default, gets claimed by usbhid module.
>> But it does not work as a HID device, instead it
>> uses a serial line logic and has a USB<=>serial
>> converter inside, which works just fine with
>> cypress_m8 usbserial driver.
>>
>> usbhid module is loaded on startup (to handle
>> usb keyboards/mouses), and it claims this device
>> too.  Using /sys/bus/.../drivers/usbhid/unbind
>> releases it, after which cypress_m8 works as
>> expected.  But after re-plugging it gets claimed
>> by usbhid again.
>
> Just add a blacklist rule to the usbhid driver for this device.  There
> are a number of devices out there that need this functionality, which is
> why there is such a list.

Is it possible to implement a generic blacklist mechanism in driver core
to support the function for all kinds of drivers? or is it necessary to do that?

Thanks!

>
>> I understand that it's easy to write an udev rule
>> (I don't use udev but that's another story) to
>> unbind the device from the driver and bind it to
>> another driver automatically.  That's basically
>> what I have for now (handling hidraw* device).
>> But that seems somewhat... ugly, at best.
>>
>> The question is: is it possible to tell usbhid
>> to STOP claiming devices with given vendor:device
>> identifier, from now on?
>>
>> I also understand that to do it permanently the
>> given vendor:device has to be blacklisted in the
>> driver source.  But I don't think it's worth the
>> effort.
>
> Why wouldn't it be worth the effort?  It's obviously a problem.
>
> thanks,
>
> greg k-h
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
>



-- 
Lei Ming
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/