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Subject: Re: [PATCH v2 2/2] pci: Support "removable" attribute for PCI
 devices
From:   Oliver Neukum <oneukum@suse.com>
To:     David Laight <David.Laight@ACULAB.COM>,
        "'Rafael J. Wysocki'" <rafael@kernel.org>
Cc:     Rajat Jain <rajatja@google.com>,
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        Rajat Jain <rajatxjain@gmail.com>,
        Jesse Barnes <jsbarnes@google.com>,
        Dmitry Torokhov <dtor@google.com>
Date:   Wed, 28 Apr 2021 08:56:52 +0200
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Am Dienstag, den 27.04.2021, 12:59 +0000 schrieb David Laight:
> From: Oliver Neukum
> > Sent: 27 April 2021 13:00

> > that is true for those options, but not for the style
> > of PCI hotplug which requires you to push a button and wait
> > for the blinking light.
> 
> True, I remember some of those PCI hotplug chassis from 25 years ago.
> ISTR we did get the removal events working (SVR4/Unixware) but I
> don't remember the relevant chassis ever being sold.
> In spite of the marketing hype I suspect it was only ever possible
> to remove a completely working board and replace it with an
> exactly equivalent one.
> 
> In any case those chassis are not 'surprise removal'.
> 
> More modern drivers are less likely to crash (and burn?) when
> a PCI read returns ~0u.
> But I suspect an awful lot really don't handle surprise removal
> very well at all.

So you are saying that these systems are so rare that it should be
handled  as special cases if at all?

	Regards
		Oliver