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Subject: Re: [PATCH/RESEND] arm64: acpi/pci: invoke _DSM whether to preserve
 firmware PCI setup
From:   Benjamin Herrenschmidt <benh@kernel.crashing.org>
To:     Bjorn Helgaas <helgaas@kernel.org>
Cc:     Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        linux-pci@vger.kernel.org, Sinan Kaya <okaya@kernel.org>,
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        linux-arm-kernel@lists.infradead.org
Date:   Thu, 13 Jun 2019 09:58:24 +1000
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On Wed, 2019-06-12 at 08:27 -0500, Bjorn Helgaas wrote:
> Speaking of which, *this* patch looks like FUD because it essentially
> says "Linux shouldn't change the PCI configuration on this system" but
> it offers no explanation of *why* the config needs to be preserved.  I
> would really like some note like "run-time firmware depends on the
> addresses of device X".

BTW. the patch doesn't say that. ACPI tells us that :-)

Cheers
Ben.