[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <Pine.LNX.4.64.0802091240160.4147@axis700.grange>
Date: Sat, 9 Feb 2008 12:41:45 +0100 (CET)
From: Guennadi Liakhovetski <g.liakhovetski@...gutronix.de>
To: David Brownell <david-b@...bell.net>
cc: linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/2] prevent gpio chip drivers from unloading while used
On Fri, 8 Feb 2008, David Brownell wrote:
> > Yes, that's what I'm saying. I had a GPIO in use and rmmod-ed pca953x. It
> > did produce an error message
> >
> > pca953x 0-0041: gpiochip_remove() failed, -16
> >
> > , but rmmod completed.
>
> Doesn't that seem buglike to you?
>
> Oh, right -- the module exit code will ignore that status, it doesn't
> even have a way to report failures any more. Crap.
>
> So it looks like we have no choice but to do this. Can you make sure
> all the rmmod-capable gpio_chip drivers support this? Ignore the SOC
> support, that never supports rmmod -- just the stuff in drivers/gpio.
As long as you find these two patches acceptable, I'll cook up an
incremental patch to fix those.
> > AFAIU, the only 2 ways currently to prevent rmmod
> > from completing, are: increment module use-count, then the respective
> > module_exit() function is not called at all and rmmod fails with -EBUSY.
> > Or block in rmmod until the resource becomes free. None of these has
> > happened. BTW, I think, there's the same problem with i2c adapter drivers.
>
> Right. In fact, every time you'd expect driver removal errors to
> cause module removal to fail. Maybe this is part of that whole
> "should we even *support* rmmod" discussion, which I tuned out.
We don't want to start another one here, do we?:-)
Thanks
Guennadi
---
Guennadi Liakhovetski
--
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/
Powered by blists - more mailing lists