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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Wed, 1 Dec 2021 21:50:34 +0100
Message-ID: <CAK8P3a2bb3w+6G4W0OAv1ASmfeOr0NTHMPpJ2An-ms2Vk7VnhQ@mail.gmail.com>
Subject: Re: [PATCH 1/5] PCI: let 'pcibios_root_bridge_prepare()' access to 'bridge->windows'
To:     Bjorn Helgaas <helgaas@kernel.org>
Cc:     Sergio Paracuellos <sergio.paracuellos@gmail.com>,
        linux-pci <linux-pci@vger.kernel.org>,
        "open list:BROADCOM NVRAM DRIVER" <linux-mips@vger.kernel.org>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        John Crispin <john@phrozen.org>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Thierry Reding <thierry.reding@gmail.com>
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On Wed, Dec 1, 2021 at 9:24 PM Bjorn Helgaas <helgaas@kernel.org> wrote:
> On Fri, Nov 19, 2021 at 05:20:17PM -0600, Bjorn Helgaas wrote:
> >
> > Arnd added this with 37d6a0a6f470 ("PCI: Add
> > pci_register_host_bridge() interface") [1].
> >
> > I can't remember why this was done, but we did go to some trouble to
> > move things around, so there must have been a good reason.
> >
> > Arnd or Thierry, do you remember?
>
> Nobody seems to remember, so I think we should go ahead and make this
> change after the usual due diligence (audit the code between the old
> site and the new site to look for any uses of bridge->windows).
>
> I think this would be material for v5.17.

Sorry I forgot to reply to your earlier mail. I think this is fine, as far as I
remember, the only reason the bridge windows are moved from the list
and added back one at a time was to preserve the exact orderorks.

We could probably even skip that step entirely and iterate throughing
that was there originally, to keep the behavior after a series of reworks.

We could probably even skip that step entirely and iterate through
bridge->windows instead of the local list to simplify this.

For Sergio's patch:

Acked-by: Arnd Bergmann <arnd@arndb.de>