Subject: Re: [2.4 patch] Port of adutux driver from 2.6 kernel to 2.4.
From: Vitaliy Ivanov <vitalivanov@gmail.com>
Reply-To: vitalivanov@gmail.com
To: Pete Zaitcev <zaitcev@redhat.com>
Cc: w@1wt.eu, gregkh@suse.de, linux-usb-devel@lists.sourceforge.net,
       linux-kernel@vger.kernel.org
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> > Didn't here anything on this? What is our final decision here?
> 
> It's gotten worse, not better. Apparently, you aren't getting the
> concept of protecting the open count with a static lock and my
> explanations are just not vivid enough or something. So I decided
> to fix it myself. Maybe then the patch in C will explain it better
> than English. But I didn't have time to do it.

Probably I'm not trying to do what you want. I analyzed locks for other
usb drivers in 2.4 tree and used same ideas.
Static lock minor_table_mutex is used for minor table structure.
And dev->sem for dev manipulations and that's why for open_count.
If you will simply browse /drivers/usb dir for 2.4 you will see that
such approach is widely used there.
What's not right?
Certainly, you have more experience so I can't say that I'm right.

> Also, there's an outright bug in the latest version. Your purge
> of the wrong lock was incomplete and so there was an unbalanced up().
> But this is moot.

Yes, got it. It's up for minor_table_mutex in adu_release. Corrected.

> So, the version before the latest is borderline acceptable. If Willy
> wants to take it, it's fine. I'll fix it up later together with 2.6.

Let's do everything correctly for 2.4.

V.

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