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Subject: Re: [edk2-devel] [PATCH] Support skipping automatic BM enumeration
To: devel@edk2.groups.io, afish@apple.com,
 Ashish Singhal <ashishsingha@nvidia.com>
Cc: "Ni, Ray" <ray.ni@intel.com>, "Wang, Jian J" <jian.j.wang@intel.com>,
 "Wu, Hao A" <hao.a.wu@intel.com>, "Gao, Zhichao" <zhichao.gao@intel.com>,
 Mike Kinney <michael.d.kinney@intel.com>
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From: "Laszlo Ersek" <lersek@redhat.com>
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Date: Tue, 5 Nov 2019 10:54:38 +0100
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On 11/05/19 07:15, Andrew Fish via Groups.Io wrote:

> You could also edit any existing variables that point to your Load File t=
o make sure they follow the rules you care about?=20
>=20
> It is legal from an UEFI spec point of view for a platform to edit the nv=
ram boot variables based on platform boot policy.=20

Good point; for example OVMF and ArmVirtQemu* do this, with the help of
QemuBootOrderLib. In essence:

- connect a particular set of devices ("ConnectDevicesFromQemu")
  - if that fails, call EfiBootManagerConnectAll()

- call EfiBootManagerRefreshAllBootOption()

- register UEFI Shell boot option manually

- filter and reorder boot options in a platform specific way
  ("RemoveStaleFvFileOptions", "SetBootOrderFromQemu")

All this happens in PlatformBootManagerAfterConsole().

Thanks,
Laszlo