files: 0.876
virtual: 0.859
device: 0.789
mistranslation: 0.726
semantic: 0.705
network: 0.626
register: 0.616
vnc: 0.615
architecture: 0.591
peripherals: 0.550
socket: 0.540
kernel: 0.524
boot: 0.523
performance: 0.522
permissions: 0.482
PID: 0.452
user-level: 0.439
risc-v: 0.438
graphic: 0.429
debug: 0.398
ppc: 0.384
arm: 0.363
VMM: 0.321
hypervisor: 0.243
TCG: 0.214
x86: 0.201
i386: 0.165
KVM: 0.123
assembly: 0.108

UEFI firmware can't write to "fake" FAT hard disk

Using the Tianocore OVMF UEFI firmware, a UEFI application cannot write to the emulated fat disk (-hda fat:rw:path/here). A file will get created or written, but will be corrupted.

Looking through old bug tickets ... When reporting issues, please provide proper information on the versions that you were using (QEMU, OVMF, ...) and complete information about which command line parameters you used to start QEMU.

Out of scope; please see my (independent, more recent) replies here:

[edk2-devel] OVMF/QEMU shell based unit tests and writing to a virtual disk

https://edk2.groups.io/g/devel/message/66655
https://edk2.groups.io/g/devel/message/66656

(alternative links:
https://www.redhat.com/archives/edk2-devel-archive/2020-October/msg00877.html
https://www.redhat.com/archives/edk2-devel-archive/2020-October/msg00878.html
)