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Date:   Mon, 31 Jul 2023 17:54:21 -0400
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Bjorn Helgaas <helgaas@kernel.org>
Cc:     Igor Mammedov <imammedo@redhat.com>, linux-kernel@vger.kernel.org,
        terraluna977@gmail.com, bhelgaas@google.com,
        linux-pci@vger.kernel.org, rafael@kernel.org,
        linux-acpi@vger.kernel.org
Subject: Re: [PATCH 1/1] PCI: acpiphp:: use
 pci_assign_unassigned_bridge_resources() only if bus->self not NULL
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References: <20230731144418.1d9c2baf@imammedo.users.ipa.redhat.com>
 <20230731214251.GA25106@bhelgaas>
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On Mon, Jul 31, 2023 at 04:42:51PM -0500, Bjorn Helgaas wrote:
> I would expect hot-add to be handled via a Bus Check to the *parent*
> of a new device, so the device tree would only need to describe
> hardware that's present at boot.  That would mean pci_root.c would
> have some .notify() handler, but I don't see anything there.

That has a big performance cost though - OSPM has no way to figure out
on which slot the new device is, so has to rescan the whole bus.