Comment 8 for bug 1931136

I was able to reproduce this w/o any chainloading. Just booting a hirsute image in QEMU w/ SecureBoot enabled was enough. I verified that I'm still seeing this issue w/ the current hirsute cloud image:

BdsDxe: loading Boot0001 "UEFI Misc Device" from PciRoot(0x0)/Pci(0x1,0x2)/Pci(0x0,0x0)
BdsDxe: starting Boot0001 "UEFI Misc Device" from PciRoot(0x0)/Pci(0x1,0x2)/Pci(0x0,0x0)
error: can't find command `hwmatch'.
EFI stub: UEFI Secure Boot is enabled.
!!!! X64 Exception Type - 06(#UD - Invalid Opcode) CPU Apic ID - 00000000 !!!!
RIP - 00000000000E0000, CS - 0000000000000038, RFLAGS - 0000000000210207
RAX - 000000007EFC5660, RCX - 000000007D18F898, RDX - 00000000000016D4
RBX - 000000007EFAFFB0, RSP - 000000007EFAFE98, RBP - 8000000000000001
RSI - 000000003DA5EC2D, RDI - 000000003FFFF1C4
R8 - 0000000000000028, R9 - 000000007E7AC267, R10 - 000000007EFAFF50
R11 - 0000000000000000, R12 - 0000000000000000, R13 - 000000007D18F898
R14 - 000000003DA58D0C, R15 - 000000007EFAFFA0
DS - 0000000000000030, ES - 0000000000000030, FS - 0000000000000030
GS - 0000000000000030, SS - 0000000000000030
CR0 - 0000000080010033, CR2 - 0000000000000000, CR3 - 000000007EC01000
CR4 - 0000000000000668, CR8 - 0000000000000000
DR0 - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000
DR3 - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400
GDTR - 000000007E9EEA98 0000000000000047, LDTR - 0000000000000000
IDTR - 000000007E401018 0000000000000FFF, TR - 0000000000000000
FXSAVE_STATE - 000000007EFAFAF0
!!!! Can't find image information. !!!!

I then mounted the image externally, updating only shim-signed:

Unpacking shim-signed (1.48+15.4-0ubuntu5) over (1.47+15.4-0ubuntu2) ...
Setting up shim-signed (1.48+15.4-0ubuntu5) ..

After that, the image booted up fine.