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Message-ID: <4773afb1ecb4d3d893b1c0e38de2f4c19694089c.camel@HansenPartnership.com>
Subject: TDX patches have broken edk2 bisectability in OVMF
From: "James Bottomley" <James.Bottomley@HansenPartnership.com>
To: Min Xu <min.m.xu@intel.com>, Jiewen Yao <jiewen.yao@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>, devel@edk2.groups.io
Date: Tue, 12 Apr 2022 17:00:00 -0400
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I've identified a serious performance regression in recent edk2, so
I've been trying to identify it by bisection, but it seems that the TDX
patches have broken bisection in edk2.  You can see this by trying to
checkout b6b2de884864 and build it.  It will give you

Active Platform          = /home/jejb/git/edk2/OvmfPkg/OvmfPkgX64.dsc
.

build.py...
/home/jejb/git/edk2/OvmfPkg/OvmfPkgX64.dsc(...): error 4000: Instance of library class [TdxLib] is not found
	in [/home/jejb/git/edk2/MdePkg/Library/BaseIoLibIntrinsic/BaseIoLibIntrinsicSev.inf] [X64]
	consumed by module [/home/jejb/git/edk2/OvmfPkg/Sec/SecMain.inf]
 

I think I can work around this, but it makes bisection extremely
painful, please don't do it again ...

James