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Date: Wed, 10 Aug 2011 14:35:11 -0400
From: "Emilio G. Cota" <cota@braap.org>
To: Martyn Welch <martyn.welch@ge.com>
Cc: "devel@driverdev.osuosl.org" <devel@driverdev.osuosl.org>,
        Greg KH <gregkh@suse.de>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 5/8] staging: vme: add functions for bridge module
 refcounting
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On Wed, Aug 10, 2011 at 10:50:59 +0100, Martyn Welch wrote:
> Again, in pci-driver.c:
> 
> static int pci_device_probe(struct device * dev)
> {
>         int error = 0;
>         struct pci_driver *drv;
>         struct pci_dev *pci_dev;
> 
>         drv = to_pci_driver(dev->driver);
>         pci_dev = to_pci_dev(dev);
>         pci_dev_get(pci_dev);
>         error = __pci_device_probe(drv, pci_dev);
>         if (error)
>                 pci_dev_put(pci_dev);
> 
>         return error;
> }
> 
> Again, doing as Manohar suggested.

Well in fact I just realised our discussion has been completely
misdirected.

I read the original patch again, and it does something different
to what these _get_dev functions are doing. The patch increments
the refcount of the _bridge_; the get_dev() calls increment the
functions of the _device_ itself, not the bridge, which wouldn't
protect the device against the bridge being removed.

The closest thing I saw in the kernel was usb_get_intf(),
which is what I had in mind when I wrote the original patchset
back in the day:

http://lxr.free-electrons.com/ident?i=usb_get_intf

Sorry for overlooking this (and the subsequent noise), it's
been a while since then.

		Emilio