From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH v2] bus/pci: fix unexpected resource mapping
	override
Date: Wed, 31 Oct 2018 19:24:21 +0100
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Cc: dev@dpdk.org, "Burakov, Anatoly" <anatoly.burakov@intel.com>, "Yigit,
 Ferruh" <ferruh.yigit@intel.com>,
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To: "Zhang, Qi Z" <qi.z.zhang@intel.com>
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30/10/2018 16:19, Zhang, Qi Z:
> From: Thomas Monjalon [mailto:thomas@monjalon.net]
> > 27/10/2018 05:20, Qi Zhang:
> > > When scanning an already plugged device, the virtual address of mapped
> > > PCI resource in rte_pci_device will be overridden with 0, that may
> > > cause driver does not work correctly.
> > > The fix is not to update any rte_pci_device's field if the being
> > > scanned device's driver is already probed.
> > >
> > > Bugzilla ID: 85
> > > Fixes: c752998b5e2e ("pci: introduce library and driver")
> > > Cc: stable@dpdk.org
> > >
> > > Reported-by: Lv Geoffrey <geoffrey.lv@gmail.com>
> > > Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
> > 
> > I still think something must be fixed in PCI scan.
> 
> We are fixing something in PCI scan, right?

Yes :)
I was thinking about not scanning an already scanned device.
If the device has been unplugged, it should be removed,
and re-added when plugged, instead of trying to update it.

I understand this is another kind of change and deserves more time
to think about the right design. That's why I will accept the v3
of this patch.

Anyway the road to get hotplug handled right is long :)