From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH v8 7/7] igb_uio: fix uio release issue for
	hotplug
Date: Tue, 10 Jul 2018 14:48:13 -0700
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To: Jeff Guo <jia.guo@intel.com>
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On Tue, 10 Jul 2018 19:03:27 +0800
Jeff Guo <jia.guo@intel.com> wrote:

>  
> +/* uio pci device state */
> +enum rte_udev_state {
> +	RTE_UDEV_PROBED,
> +	RTE_UDEV_OPENNED,
> +	RTE_UDEV_RELEASED,
> +	RTE_UDEV_REMOVED,
> +};
> +

The states here are a little confusing. especially since pci_release
seems to take different actions based on the state. And there is nothing
preventing races between unexpected removal (PCI), and removing the
device from being used by igb_uio.

Would it be possible to only use state variable from the kernel PCI
layer where the value is consistent?

Also there is refcounting in PCI layer (and locking). Could that
be used instead?