Date: Thu, 09 Sep 2004 14:55:39 +0900
From: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Subject: Re: [PATCH] missing pci_disable_device()
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To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: greg@kroah.com, akpm@osdl.org, bjorn.helgaas@hp.com,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Alan Cox wrote:
> On Mer, 2004-09-08 at 04:14, Kenji Kaneshige wrote:
>> > Think about unloading frame buffers or PCI devices with multiple
>> > functions and multiple drivers. I agree the drivers definitely want
>> > fixing where appropriate. I'm not sure your approach is safe (although a
>> 
>> I don't understand what you are worried about. Could you tell me
>> what would be a problem with frame buffers or PCI devices with
>> multiple functions?
> 
> If I have a framebuffer driver loaded for my video card in bitmap mode
> all is well. If I unload it you then disable the video hardware even
> though it would still be otherwise usable in text mode.
> 
> The same occurs when one PCI device has multiple functions (not PCI
> functions but linux drivers using it). There are some examples of this
> such as the CS5520 where one BAR is the IDE controller.
> 

Thank you for answering.

I understand that there are some devices that need to be enabled
even after their drivers are unloaded, and my approach might not
be safe in this case. I think the best way to solve the problem
(missing pci_disable_device) is to fix broken drivers one by one.
I think debug printk will helpful to fix those drivers, but I
don't know what kind of message is appropriate...

Thanks,
Kenji Kaneshige


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