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Date: Fri, 6 Jan 2006 18:53:52 +0000
From: Russell King <rmk+lkml@arm.linux.org.uk>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>, Linux Kernel list <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@osdl.org>
Subject: Re: Platform device matching, & weird strncmp usage
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On Fri, Jan 06, 2006 at 04:59:39PM +1100, Benjamin Herrenschmidt wrote:
> static int platform_match(struct device * dev, struct device_driver * drv)
> {
> 	struct platform_device *pdev = container_of(dev, struct platform_device, dev);
> 
> 	return (strncmp(pdev->name, drv->name, BUS_ID_SIZE) == 0);
> }
> 
> As far as I know, strncmp() is _NOT_ supposed to return 0 if one string
> is shorter than the other and they match until that point. Thus the
> above will never match unless the <name> portion of pdev->name is
> exactly of size BUS_ID_SIZE which is obviously not the case...

pdev->name is just the <name> part - it's pdev->dev.name which has
both the <name> and <instance>.  I think the strncmp is unnecessary,
and it can be replaced by a plain strcmp.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 Serial core
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