Concern with log output from grub-mkconfig

Skeleton2323 · 2025-07-08 15:54:59

I have a dual-booted UEFI Windows + Arch setup with GRUB (fast startup is disabled on windows )
After resetting my PC's CMOS, all of the UEFI entries were reset and only the Windows Boot Manager was automatically set up by presumably the firmware.
I used Ventoy to manually choose the grub efi file on the efi partition to manually boot up Arch and when it booted up successfully, I wanted to add back the GRUB entry.

Since I had already mounted the EFI partition, I ran

sudo grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=Apsida

which resulted in the process finishing with "Installation completed with no errors"

and then

sudo  grub-mkconfig -o /boot/grub/grub.cfg

with this log

Generating grub configuration file ...
Found theme: /boot/grub/themes/OldBIOS/theme.txt
Found linux image: /boot/vmlinuz-linux
Found initrd image: /boot/initramfs-linux.img
Found fallback initrd image(s) in /boot:  initramfs-linux-fallback.img
Warning: os-prober will be executed to detect other bootable partitions.
Its output will be used to detect bootable binaries on them and create new boot entries.
Found Windows Boot Manager on /dev/nvme0n1p1@/EFI/Microsoft/Boot/bootmgfw.efi
Found linux image: /boot/vmlinuz-linux
Found initrd image: /boot/initramfs-linux.img
Found fallback initrd image(s) in /boot:  initramfs-linux-fallback.img
Adding boot menu entry for UEFI Firmware Settings ...
Found memtest86+ EFI image: /boot/memtest86+/memtest.efi
/usr/bin/grub-probe: warning: unknown device type nvme0n1.
done

While GRUB reinstallation was a success, the line /usr/bin/grub-probe: warning: unknown device type nvme0n1 seems odd to me. Could you please tell me what it could possibly mean and why it's outputted even though everything seemed to work?
If you need any logs, I can provide them

SimonJ · 2025-07-08 16:07:58

Is the EFI partition on a different drive? I had this before when I wrote the Arch EFI details into the existing windows EFI partition, but it all still worked.

Skeleton2323 · 2025-07-08 16:24:21

The EFI partition is on the same drive as the root directory and the grub efi file coexists with the windows one on different directories

This is how my drive partition table looks like

nvme0n1     259:0    0 465,8G  0 disk 
├─nvme0n1p1 259:1    0   100M  0 part /boot/efi
├─nvme0n1p2 259:2    0    16M  0 part 
├─nvme0n1p3 259:3    0   309G  0 part 
├─nvme0n1p4 259:4    0 156,1G  0 part /
└─nvme0n1p5 259:5    0   525M  0 part

SimonJ · 2025-07-09 04:27:55

Do you now have two EFI partitions? What does sudo fdisk -l
show?

Skeleton2323 · 2025-07-09 14:35:02

No, I have two drives, only one is bootable and only one has an EFI partition

fdisk -l

Disk /dev/sda: 3,64 TiB, 4000787030016 bytes, 7814037168 sectors
Disk model: WDC WD40EZAZ-00S
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: C4B29E7E-CA72-4084-918D-7BD673467A94

Device     Start        End    Sectors  Size Type
/dev/sda1  32768 7814033407 7814000640  3,6T Microsoft basic data


Disk /dev/nvme0n1: 465,76 GiB, 500107862016 bytes, 976773168 sectors
Disk model: Samsung SSD 980 500GB                   
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 16384 bytes / 131072 bytes
Disklabel type: gpt
Disk identifier: 7FEF8016-0880-11EF-9749-7824AFBC0B93

Device             Start       End   Sectors   Size Type
/dev/nvme0n1p1      2048    206847    204800   100M EFI System
/dev/nvme0n1p2    206848    239615     32768    16M Microsoft reserved
/dev/nvme0n1p3    239616 648312831 648073216   309G Microsoft basic data
/dev/nvme0n1p4 648312832 975695871 327383040 156,1G Linux filesystem
/dev/nvme0n1p5 975695872 976771071   1075200   525M Windows recovery environment

SimonJ · 2025-07-09 15:37:21

Sorry I cannot explain further, it seems to have been showing this warning a while with windows dual boot https://bbs.archlinux.org/viewtopic.php?id=230961

It seems not cause problems though, I no longer have windows and the error has also gone.

Skeleton2323 · 2025-07-09 16:40:19

Fair enough
I can't recall seeing this message on this installation and on this computer with this exact hardware configuration beforehand though

seth · 2025-07-10 14:16:37

https://savannah.gnu.org/bugs/?56669

file -s /dev/nvme0n1

But the message shows up like a gazillion times on google - it's just noise.

Skeleton2323 · 2025-07-10 23:41:22

file -s /dev/nvme0n1

/dev/nvme0n1: DOS/MBR boot sector; partition 1 : ID=0xee, start-CHS (0x0,0,2), end-CHS (0x3ff,255,63), startsector 1, 976773167 sectors

(mbr shows up? i'm pretty sure the drive has a guid partition table)
EDIT: right, it's ID=0xee so GPT, no?

also I found this forum post regarding the same error on garuda and an answer suggests it's a side effect of having memtest installed, which I do as well
https://forum.garudalinux.org/t/unknown … n1/26361/2

Last edited by Skeleton2323 (2025-07-10 23:42:47)

seth · 2025-07-11 07:06:28

Yes, is GPT. The file output is unsuspicious (as is suggested by all occurrences of the warning, including in the garuda thread blaming memtest)
You could wrap /etc/grub.d/60_memtest86+ in

set -x
…
set +x

to trace the cause.

Arch Linux

#1 2025-07-08 15:54:59

Concern with log output from grub-mkconfig

#2 2025-07-08 16:07:58

Re: Concern with log output from grub-mkconfig

#3 2025-07-08 16:24:21

Re: Concern with log output from grub-mkconfig

#4 2025-07-09 04:27:55

Re: Concern with log output from grub-mkconfig

#5 2025-07-09 14:35:02

Re: Concern with log output from grub-mkconfig

#6 2025-07-09 15:37:21

Re: Concern with log output from grub-mkconfig

#7 2025-07-09 16:40:19

Re: Concern with log output from grub-mkconfig

#8 2025-07-10 14:16:37

Re: Concern with log output from grub-mkconfig

#9 2025-07-10 23:41:22

Re: Concern with log output from grub-mkconfig

#10 2025-07-11 07:06:28

Re: Concern with log output from grub-mkconfig

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