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Date: Fri, 15 Aug 2014 21:19:18 -0700
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Rob Herring <robherring2@gmail.com>
Cc: Stepan Moskovchenko <stepanm@codeaurora.org>,
        Grant Likely <grant.likely@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        linux-arm-msm <linux-arm-msm@vger.kernel.org>
Subject: Re: [PATCH v2] of: Deep-copy names of platform devices
Message-ID: <20140816041918.GE14338@kroah.com>
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On Fri, Aug 15, 2014 at 11:38:33AM -0500, Rob Herring wrote:
> Adding Greg...
> 
> On Tue, Aug 12, 2014 at 9:30 PM, Stepan Moskovchenko
> <stepanm@codeaurora.org> wrote:
> > When we parse the device tree and allocate platform
> > devices, the 'name' of the newly-created platform_device
> > is set to point to the 'name' field of the 'struct device'
> > embedded within the platform_device. This is dangerous,
> > because the name of the 'struct device' is dynamically
> > allocated. Drivers may call dev_set_name() on the device,
> > which will free and reallocate the name of the device,
> > leaving the 'name' of the platform_device pointing to the
> > now-freed memory.
> >
> > Furthermore, if the dev_set_name() call is made from a
> > driver's probe() function and a subsequent request results
> > in probe deferral, the dangling 'name' reference may lead
> > to the device being re-probed using the wrong driver.
> 
> This seems wrong. I don't think we want drivers to change their own
> device's name. The name is not supposed to change after registration.

That is correct.  Well, you can change a name, using device_rename(),
but that's the only way to do it, not through dev_set_name(), as is
pointed out here, that will cause problems.

So I don't think this patch is needed at all.

thanks,

greg k-h