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Date:   Tue, 6 Jul 2021 01:02:12 +0200
From:   Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kw@linux.com>
To:     Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
Cc:     Aaron Ma <aaron.ma@canonical.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        jesse.brandeburg@intel.com, anthony.l.nguyen@intel.com,
        davem@davemloft.net, kuba@kernel.org,
        intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org,
        Marek =?utf-8?B?QmVow7pu?= <kabel@kernel.org>
Subject: Re: [PATCH 1/2] igc: don't rd/wr iomem when PCI is removed
Message-ID: <20210705230212.GC142312@rocinante>
References: <20210702045120.22855-1-aaron.ma@canonical.com>
 <20210704142808.f43jbcufk37hundo@pali>
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Hi Pali,

[...]
> Aaron: can you check if pci_dev_is_disconnected() is really something
> which should be used and it helps you?

While having a closer look, I've noticed that quite a few of the network
drivers handle this somewhat, as I see that a lot of them have some sort
of I/O error handles set where a check for "pci_channel_io_perm_failure"
seem to be having place.  This is also true for this driver looking at
the igc_io_error_detected().

Is this not working for the igc driver?  Or is this for something
completely different?

Having said all that, I am not an expert in network drivers, so pardon
me if I am asking about something completely different, and I apologise
if that is the case.

> Bjorn, Krzysztof: what do you think about lifting helper function
> pci_dev_is_disconnected() to be available to all drivers and not only in
> PCI subsystem?

No objections from me, if we believe it's useful and that it might
encourage people to use a common API.  Currently, I can see at least
five potential users of this helper.

	Krzysztof