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Date: Sat, 2 Oct 2010 18:28:39 +0800
Message-ID: <AANLkTim1SDjhautuTiSO5hStD3qAKa5GUanF3aP51UYT@mail.gmail.com>
Subject: Re: [PATCH] usb: core: endpoint: Fix error path
From: Ming Lei <tom.leiming@gmail.com>
To: Rahul Ruikar <rahul.ruikar@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>, Tejun Heo <tj@kernel.org>,
        asanchez@neurowork.net, rjw@sisk.pl, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org
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2010/10/2 Rahul Ruikar <rahul.ruikar@gmail.com>:
> Thanks Ming.
> I have certain doubts related to device_unregister()
>
> In some of USB related code..
> kfree() is called after device_unregister() ...  device_unregister()
> also internally calls put_device()... is that correct behavior or I'm
> missing something here..

If no other external reference to device before put_device in device_unregister,
dev.release will be called from put_device to free something, which depends
on your implement for dev.release.

> ex.
> file : drivers/usb/gadget/fsl_udc_core.c
> function : static int __init fsl_udc_probe(struct platform_device *pdev)

Once reaches err_unregister, double free of udc_controller may be
triggered, so fix should be needed.

-- 
Lei Ming