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From:   Bjorn Helgaas <bhelgaas@google.com>
Date:   Mon, 4 Mar 2019 14:11:57 -0600
Message-ID: <CAErSpo4U6Kys5OzPwfyFdbnJWfTZ-y0P830okf11BwfNv9Y82A@mail.gmail.com>
Subject: Re: [PATCH 1/2] PCI: Prevent 64-bit resources from being counted in
 32-bit bridge region
To:     Logan Gunthorpe <logang@deltatee.com>
Cc:     Bjorn Helgaas <helgaas@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux PCI <linux-pci@vger.kernel.org>,
        Kit Chow <kchow@gigaio.com>, Yinghai Lu <yinghai@kernel.org>
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On Mon, Mar 4, 2019 at 1:21 PM Logan Gunthorpe <logang@deltatee.com> wrote:
> On 2019-03-03 5:23 p.m., Bjorn Helgaas wrote:
> > Sorry for the delay.  This code gives a headache.  I still remember
> > my headache from the last time we touched it.  Help me understand
> > what's going on here.
>
> Yes, this code gave me a headache debugging it too. And it's not the
> first time I've tried to figure out what's going on with it because it
> often just prints noisy messages that look like errors. I think I
> understand it better now but it's something that's a bit fleeting and
> easy to forget the details of. There may also be other solutions to this
> problem.

Thanks for the explanation below.  I haven't worked through it yet, but I will.

Obviously it would be far better than an explanation if we could
simplify the code (and the noisy messages) such that it didn't
*require* so much explanation.

Bjorn