id = 1074
title = "File under symlink gets corrupted when directory is mounted as FAT32 drive"
state = "opened"
created_at = "2022-06-12T14:23:16.339Z"
closed_at = "n/a"
labels = ["Storage"]
url = "https://gitlab.com/qemu-project/qemu/-/issues/1074"
host-os = "Fedora 36"
host-arch = "x86_64"
qemu-version = "6.2.0 (qemu-6.2.0-11.fc36)"
guest-os = "handwritten"
guest-arch = "x86_64"
description = """When mouting a directory as a FAT32 drive, the symlinked BOOTx64.EFI inside gets corrupted after booting it."""
reproduce = """1. mkdir -p fat_dir/EFI/BOOT/
2. ln -s BOOTx64.EFI fat_dir/EFI/BOOT/BOOTx64.EFI
3. md5sum BOOTx64.EFI
4. Run qemu with arguments like above.
5. md5sum BOOTx64.EFI should print out different hash, confirming corruption."""
additional = """[BOOTx64.EFI](/uploads/d0a6e899ec9331461179f8dc82fbc421/BOOTx64.EFI)

The issue was not visible on earlier versions, but I don't know which one exactly was it.\\
I can only say, it was still working in April and it was possible that I was using Fedora 36 Beta.

Copying the file instead of using a symlink can be used as a workaround.

The binary should print some debug stuff, like avaliable memory regions and end with an infinite halt-loop."""