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Date:   Fri, 21 Jan 2022 16:45:25 +0100
From:   Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
To:     Martin =?utf-8?B?TWFyZcWh?= <mj@ucw.cz>
Cc:     Bjorn Helgaas <helgaas@kernel.org>,
        Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kw@linux.com>,
        Matthew Wilcox <willy@infradead.org>, linux-pci@vger.kernel.org
Subject: Re: [PATCH pciutils 0/5] Support for PROGIF, REVID and SUBSYS
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On Friday 21 January 2022 16:38:50 Martin Mareš wrote:
> > And in case "class+subclass+prog_if" is available but "revision" is not
> > available and even it is not possible to read revision from config space
> > (because e.g. due to missing permissions or limitations of win backend)?
> 
> I bet that nobody will ever check if reading of something as basic as the
> revision ID succeeded. It can never fail on sane systems.
> 
> In such cases, just return a default value and log a warning.

Ok! Sorry for a longer discussion as it is only corner case, but it can
happen (probably more often happens on windows) and therefore needs to
be somehow handled in the code.