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Subject: Re: [edk2-devel] [Patch V3 2/2] MdeModulePkg/Bus/Pci/PciBusDxe: Support PCIe Resizable BAR Capability
From: "Laszlo Ersek" <lersek@redhat.com>
To: devel@edk2.groups.io, heng.luo@intel.com
Cc: Ray Ni <ray.ni@intel.com>, Hao A Wu <hao.a.wu@intel.com>
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Date: Mon, 11 Jan 2021 20:44:30 +0100
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Hi Heng,

On 01/11/21 20:38, Laszlo Ersek wrote:

> General request for the future: if you implement some kind of policy in
> core edk2, please at least *document* the policy somewhere. It's
> unacceptable to have to decipher the source code for such a possibly
> impactful change in the core. There is no need for a wiki page or an
> RFC, but a sane bugzilla ticket and a sane commit message are required.
> 
> (The documentation of the PCD in the "MdeModulePkg.dec" file is
> unsatisfactory too, and the UNI file has not been updated at all.)

Wow, I've even found the following regression in the bug tracker:

  https://bugzilla.tianocore.org/show_bug.cgi?id=3158

Your approach in

  https://bugzilla.tianocore.org/show_bug.cgi?id=3158#c1

is entirely wrong. It is not the burden of platform owners to fix up the
regression you have introduced. It is your responsibility to *not break*
existent use cases. You can offer the feature, and platforms that want
the feature may enable it (or you can enable it by default if you can
prove or test that no platform breaks in response).

Please revert this patch immediately, or flip the PCD default to FALSE
immediately.

Laszlo