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Date: Mon, 4 Feb 2008 08:14:37 -0800
From: Greg KH <greg@kroah.com>
To: Adrian McMenamin <adrian@newgolddream.dyndns.info>
Cc: Paul Mundt <lethal@linux-sh.org>, linux-sh <linux-sh@vger.kernel.org>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] SH/Dreamcast - fix regressions, whitespace and memory
	leaks in Maple Bus driver
Message-ID: <20080204161437.GA20739@kroah.com>
References: <1202068847.6262.7.camel@localhost.localdomain> <20080204052900.GB7585@kroah.com> <1202113675.6489.6.camel@localhost.localdomain>
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On Mon, Feb 04, 2008 at 08:27:55AM +0000, Adrian McMenamin wrote:
> 
> On Sun, 2008-02-03 at 21:29 -0800, Greg KH wrote:
> > On Sun, Feb 03, 2008 at 08:00:47PM +0000, Adrian McMenamin wrote:
> > > From: Adrian McMenamin
> > > 
> > > This patch fixes the regression noted here:
> > > http://lkml.org/lkml/2008/1/26/189 as well as whitespace issues in the
> > > previous commit of this driver and the memory leaks noted here:
> > > http://lkml.org/lkml/2008/2/2/143 (as well as one or two other minor
> > > cleanups).
> > 
> > Which portion of the patch fixes the kobject WARN_ON()?
> 
> 
> 
> +	if (mdev->registered == 0) {
> +		retval = device_register(&mdev->dev);
> +		if (retval) {
> +			printk(KERN_INFO
> +			"Maple bus: Attempt to register device"
> +			" (%x, %x) failed.\n",
> +			mdev->port, mdev->unit);
> +			maple_free_dev(mdev);
> +			mdev = NULL;
> +			return;
> +		}
> +		mdev->registered = 1;
> +	}
>  }
> 
> 
> Specifically the check on mdev->registered

So the code path could cause devices to be registered more than once?
That seems broken, as no other bus that I know of needs such a check :(

Is there a way to fix the root problem here, instead of this type of
change?

thanks,

greg k-h