Unable to boot UEFI from 2.04

[David Huffman]

I have built 2.04 from source (no errors). I have a script to create a 
BIOS/UEFI bootable hard drive. The grub-install command I am running succeeds 
without errors, but the kernel does not seem to execute when booting from UEFI 
(BIOS is fine).

Adding debug=all to the configuration file shows the execution stops at:
(...last three lines)

diskefiefidisk.c:595: reading 0x40 sectors at sector 0x48dc0 from hd1
diskefiefidisk.c:595: reading 0x40 sectors at sector 0x48e00 from hd1
diskefiefidisk.c:595: reading 0x40 sectors at sector 0x48e40 from hd1

If I use the grub /usr/lib/grub/x86_64-efi files (*.mod, kernel.img, etc) 
poached from Debian 10.5, the system executes the kernel properly. If I just 
swap out the x86_64-efi directory with the files I compiled, the kernel does 
not execute. I am using the grub-install program I compiled from source in both 
cases.The only difference are the files in lib/grub/x86_64-efi/.

I have found references that linuxefi.mod was removed from grub and is a 
“distro patch”. This module appears to be missing from by source build but 
removing it from the debian grub files didn’t seem to make a difference.

Here are the commands used to build:

configure --with-platform=efi --target=x86_64 --disable-device-mapper 
—prefix=$GRUBDIR
make
make install

Inside $GRUBDIR I have all of the files I would expect from the build.

The disk has three partitions with an msdos partition table:

# sfdisk -l /dev/sdb

Disk /dev/sdb: 1305 cylinders, 255 heads, 63 sectors/track
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

   Device Boot Start     End   #cyls    #blocks   Id  System
/dev/sdb1   *      0+     12-     13-    102400   83  Linux     
/dev/sdb2         12+     25-     13-    102400   83  Linux
/dev/sdb3         25+   1305-   1280-  10279936   83  Linux
/dev/sdb4          0       -       0          0    0  Empty

/dev/sdb2 on /mnt type ext2 (rw)
/dev/sdb1 on /mnt/boot/EFI type vfat (rw)

Here is the grub-install commands used:

FOR BIOS:
grub-install —force --boot-directory=$TMPMNT/boot --target=i386-pc 
—directory=$GRUBDIR/i386-pc  /dev/sdb

FOR UEFI       
grub-install --removable --efi-directory=$TMPMNT/boot/EFI 
--boot-directory=$TMPMNT/boot --target=x86_64-efi 
--directory=$GRUBDIR/x86_64-efi /dev/sdb

At this point I am not sure what else to look at to find out what is different 
between the modules and kernel.img file I compile and what is supplied with 
debian. Any assistance in tracking down the problem would be appreciated.


 - David