fwiw, I'm able to reproduce the slow-to-boot-ISO issue by using IDE. With that as a symptom, I completed the bisect and hit:
6fb8ddd36bde MdeModulePkg/AtaAtapiPassThru: disable the device at ExitBootServices()
Prior to this commit, it took 34s for me to go from EFI shell to first install screen.
With this commit, it takes 8.5 minutes. I tried to complete an install in this mode but gave up after an hour w/ the installer hung at 10% in "preparing files for install."
fwiw, I'm able to reproduce the slow-to-boot-ISO issue by using IDE. With that as a symptom, I completed the bisect and hit:
6fb8ddd36bde MdeModulePkg/ AtaAtapiPassThr u: disable the device at ExitBootServices()
Prior to this commit, it took 34s for me to go from EFI shell to first install screen.
With this commit, it takes 8.5 minutes. I tried to complete an install in this mode but gave up after an hour w/ the installer hung at 10% in "preparing files for install."