The symptom is that enabling the mender-grub feature on vexpress-qemu does not work.
This is the key commit:
Author: Heinrich Schuchardt <firstname.lastname@example.org>
Date: Mon Apr 22 00:06:20 2019
efi_loader: disable EFI_LOADER on vexpress_ca15_tc2 and ca9x4
vexpress_ca15_tc2_defconfig and vexpress_ca9x4_defconfig do not provide
device trees (as $fdtcontroladdr) as needed to pass our Travis CI tests.
As we are on the move to requiring block devices to be based on the driver
model these boards either will have to be converted to use device trees or
will be kicked out of U-Boot.
So let's disable CONFIG_EFI_LOADER on these boards until the device tree
issue is resolved.
Signed-off-by: Heinrich Schuchardt <email@example.com>
However, it is not as easy as simply adding it back. There are several restructurings in U-Boot, and it doesn't appear to be possible to load GRUB without a device tree as it previously was.
The problem is exclusive to QEMU, but because of our heavy reliance on it for testing, it is very important.
It's related to, but not the same, as