linux-kernel - Re: [PATCH 4.19 089/219] ipmi: Dont allow device module unload when in use

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Message-ID: <20191231213255.GC6497@minyard.net>
Date:   Tue, 31 Dec 2019 15:32:55 -0600
From:   Corey Minyard <cminyard@...sta.com>
To:     Pavel Machek <pavel@...x.de>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-kernel@...r.kernel.org, stable@...r.kernel.org,
        tony camuso <tcamuso@...hat.com>,
        Sasha Levin <sashal@...nel.org>
Subject: Re: [PATCH 4.19 089/219] ipmi: Dont allow device module unload when
 in use

On Mon, Dec 30, 2019 at 11:32:18AM +0100, Pavel Machek wrote:
> On Sun 2019-12-29 18:18:11, Greg Kroah-Hartman wrote:
> > From: Corey Minyard <cminyard@...sta.com>
> > 
> > [ Upstream commit cbb79863fc3175ed5ac506465948b02a893a8235 ]
> > 
> > If something has the IPMI driver open, don't allow the device
> > module to be unloaded.  Before it would unload and the user would
> > get errors on use.
> > 
> > This change is made on user request, and it makes it consistent
> > with the I2C driver, which has the same behavior.
> > 
> > It does change things a little bit with respect to kernel users.
> > If the ACPI or IPMI watchdog (or any other kernel user) has
> > created a user, then the device module cannot be unloaded.  Before
> > it could be unloaded,
> > 
> > This does not affect hot-plug.  If the device goes away (it's on
> > something removable that is removed or is hot-removed via sysfs)
> > then it still behaves as it did before.
> 
> I don't think this is good idea for stable. First, it includes
> unrelated function rename,

Umm, no, that's not unrelated, it was renamed so a defined could be
done with the original name so the module could be passed in
automatically.

> and second, it does not really fix any bug;
> it just changes behaviour.

This is true.  I assume Tony asked for the backport.  I'm ambivolent
on whether this gets backported.  I'll defer to Tony for justification.

-corey

> 
> Best regards,
> 									Pavel
> -- 
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html