Dear Nicolas,
thanks for your response, it helped a lot. You are totally right.
https://bugs-devel.debian.org/cgi-bin/bugreport.cgi?bug=1058818&pow_referer=
I still do not understand why the problem occurred for me just after
the update of Debian 13 last week, as I am using Trixie since it was
released, approximately a year ago.
At least, my problem is solved, and was known to the community.
Thanks again,
Nicolas
On 9/17/26 14:10, Nicolas George wrote:
Coin (HE12026-09-17):
After updating my debian 13 last week-end, when I restart my computer, it
launches GRUB as usual, but immediately reboots after GRUB had just the time
to display a first line, but not even the menuentries. Therefore, I was not
able to log in into my debian because it reboots at infinity.
I found this:
### BEGIN /etc/grub.d/30_uefi-firmware ###
if [ "$grub_platform" = "efi" ]; then
fwsetup --is-supported
if [ "$?" = 0 ]; then
menuentry 'UEFI Firmware Settings' $menuentry_id_option 'uefi-firmware' {
fwsetup
}
fi
fi
### END /etc/grub.d/30_uefi-firmware ###
to be the cause of the problem, and since from my point of view these lines
I had the same issue with my virtual machines: I have a small image file
with GRUB on a single EFI partition that just tries to load grub.cfg
from the next disk; that way the other volumes of the VM can be
unpartitioned, it is much more convenient. It worked fine with Bookworm
VMs but it started rebooting like you describe.
The cause of the problem is that (1) Bookworm's GRUB does not know the
--is-supported option and (2) it ignores unknown options instead of just
printing an error. Hence, the test itself was causing the reboot.
The issue was fixed by generating a new EFI image with Trixie's GRUB on
it. It works well with Bookworm VMs too.
This command queries an EFI variable (|OsIndicationsSupported|) to check
whether the firmware supports rebooting directly into its configuration
interface. This is a fairly common UEFI bug (seen on some Dell, HP, Lenovo,
ASUS firmwares...): this simple |GetVariable| query causes the firmware to
crash, which responds by forcing an immediate reset of the machine.
I do not think this reply is accurate.
I suggest you try to fix your issue with simply with grub-install, and
only suspect an actual firmware bug if it is not enough.
Regards,
