GRUB UEFI boot entries wiped — rEFInd kernel panic, manual GRUB boot fails on Btrfs subvol @ — MSI Cyborg 15

English Install/Boot/Login
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System: MSI Cyborg 15 A12UDX (BIOS E15K1IMS.315)
OS: openSUSE Tumbleweed on /dev/nvme0n1p2 (Btrfs with @ subvolume)

What happened:
Windows/Grub2Win removal wiped UEFI NVRAM boot entries. System now drops into grub> 2.12 shell every boot.

What I tried:

  1. rEFInd — detects kernel vmlinuz-7.1.5-1-default but panics with:
    VFS: Unable to mount root fs on unknown-block(0,0)
    I added root=/dev/nvme0n1p2 rootflags=subvol=@ rw via F2 but still panics.

  2. Manual grub> boot — tried:
    linux /@/boot/vmlinuz... root=/dev/nvme0n1p2 rootflags=subvol=@ rw
    initrd /@/boot/initrd...
    Got file-not-found errors.

  3. Rescue USB — grub2-install, update-bootloader --reinit, efibootmgr all failed to restore boot. Suspect MSI NVRAM is buggy/locked.

Current state: All files on /dev/nvme0n1p2 are safe. Just missing UEFI boot entries.

Need help with:

  • Exact grub> manual boot commands for openSUSE Btrfs @ layout
  • Correct rEFInd parameters to pass root + initrd
  • Reliable GRUB reinstall for MSI boards with broken NVRAM

I can boot a live rescue USB. Any help appreciated!

1 Like
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Have you tried getting into the BIOS & then setting it to boot from your nvme0n1p2 in there? Usually have to hold down del key or f2 or sometimes f4. It may say what key to press on your initial power up screen. If that works you might be able to rebuild grub from there if you need it, but it sounds like you removed Windows from what you said - so do you need grub if you are just booting into openSUSE? Hope this might help?

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Please start the rescue system in UEFI-only boot mode (not in CSM aka Legacy-mode and not in UEFI+CSM), execute the following commands and show the complete results (i.e. command executed + all results + new, empty command prompt) here

lsblk -f -o NAME,PTTYPE,PARTTYPE,UUID,LABEL,FSTYPE,MOUNTPOINTS,FSSIZE,FSUSE%,HOTPLUG

efibootmgr

bootctl
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susejunky is a high-ranking community member (Wise Penguin) — this is exactly the kind of expert you want helping you. But they asked for rescue USB output, and you don’t have one.

Here’s what to do:

Option 1: Try Booting the SUSE_INSTAL Partition (No USB Needed!)

Remember that partition we saw?

  • (hd0,gpt5) [SUSE_INSTAL] ntfs 9.77G

That might be a rescue/recovery environment left over from your openSUSE installation. Try this:

  1. In rEFInd, go back to the partition list
  2. Select (hd0,gpt5) [SUSE_INSTAL]
  3. Press Enter to boot it

If it boots into a rescue system, you can run the commands susejunky asked for right there.

Option 2: Reply to susejunky Now (No USB)

If the SUSE_INSTAL partition doesn’t boot, reply to the forum with this. It gives them all the diagnostic info you’ve already gathered:

Hi susejunky, thanks for the reply. I don’t actually have a USB pen drive available right now, but I can provide the following info from rEFInd and the grub> shell:

System: MSI Cyborg 15 A12UDX, BIOS E15K1IMS.315 (09/2024)

Partition layout (from rEFInd):

  • (hd0,gpt1) fat 600M — EFI partition
  • (hd0,gpt2) btrfs 465.8G — openSUSE root
  • (hd0,gpt5) ntfs 9.77G — labeled “SUSE_INSTAL”

EFI partition contents: No /efi/opensuse/ folder exists — it was wiped along with the NVRAM entries. Only /efi/boot/ (rEFInd) and /efi/grub2win/ (old Grub2Win files) remain.

Current state: System drops into grub> 2.12 shell. rEFInd detects vmlinuz-7.1.5-1-default on gpt2 but booting it panics with VFS: Unable to mount root fs on unknown-block(0,0) even after adding root=/dev/nvme0n1p2 rootflags=subvol=@ rw. I suspect rEFInd isn’t loading the initrd.

What I’ve tried: grub2-install, update-bootloader --reinit, and efibootmgr from a previous rescue attempt all failed to restore boot entries. Suspect MSI NVRAM is buggy/locked.

Question: Is there any way to boot manually from the grub> prompt using the correct Btrfs @ subvolume paths for kernel + initrd? Or can the SUSE_INSTAL partition (gpt5) be used as a rescue source without a USB?

I can take photos of any screen output needed. Thanks!

Option 3: Try the grub> Shell One More Time

Before you reply, try this exact sequence at the grub> prompt and tell me the output:

set root=(hd0,gpt2)
ls /@/boot/

Use Tab after vmlinuz- and initrd- to see the exact filenames. Then try:

linux /@/boot/vmlinuz-[TAB-complete] root=/dev/nvme0n1p2 rootflags=subvol=@ rw
initrd /@/boot/initrd-[TAB-complete]
boot

If this works, you won’t need the forum rescue at all.

What do you want to try first? The SUSE_INSTAL partition, the grub> shell, or just reply to the forum?

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I am not a cs background student using ai chat boat

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And that AI bot is putting out nonsense AFAICS. I am not going to debate such bot results.

2 Likes
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Then why didn’t you do just that to show the results I asked for?

1 Like
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Eh, “AI bot says” first?

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Hi susejunky and knurpht, sorry for the confusion. I don’t have a USB pen drive, so I tried the SUSE_INSTAL partition on my disk instead. The rescue shell there is extremely minimal — btrfs , efibootmgr , and grub2-install are all not found.
I then tried booting via rEFInd and the UEFI Shell, but the opensuse EFI folder was wiped. Here are the of what I found:

  1. Partition layout ( lsblk -f ):

nvme0n1p1 = vfat (EFI, 600M)

nvme0n1p2 = btrfs (openSUSE root, 465G)

nvme0n1p5 = ntfs (SUSE_INSTAL, 9.77G)
2. EFI partition contents: No /efi/opensuse/ folder. Only /efi/boot/ (rEFInd) and /efi/grub2win/ (old files) remain.
3. Current state: System drops into grub> 2.12 shell on every boot.

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Hi @susejunky, knurpht — sorry for the back and forth. I don’t have a USB pen drive, so I tried the SUSE_INSTAL partition on disk. The rescue shell there is extremely minimal: btrfs , efibootmgr , and grub2-install are all command not found.
What I did: I already downloaded and installed openSUSE Tumbleweed. The install completed, but after reboot there is no openSUSE boot option — the system drops straight into the minimal grub> 2.12 shell.
What I found:

nvme0n1p1 = vfat (EFI, 600M) — no /efi/opensuse/ folder, only /efi/boot/ (rEFInd) and old /efi/grub2win/

nvme0n1p2 = btrfs (465G) — my openSUSE root with @ subvolume

nvme0n1p5 = ntfs ( SUSE_INSTAL , 9.77G)
Current state: Every boot loops to grub> shell. I can use ls and Tab completion in GRUB.
Request: Can someone give me the exact grub> commands to manually boot from the Btrfs @ subvolume? I can take photos of any grub> output needed.
Thanks for your patience.

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When start after restart this show

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When i click on penguin, this show, @susejunky @knurpht @jjis

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Refind != openSUSE. No idea where and why it comes in.

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Two months ago, I was on Fedora Workstation. I used rEFInd to switch back to Windows. Recently, I used Grub2Win to install openSUSE, and the installation was successful. However, after rebooting, there’s no option to boot into openSUSE, and rEFInd just shows up instead @knurpht

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It is quite unlikely that a NTFS partition has anything to do with an openSUSE installation…

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I am not familiar with rEFInd or Grub2Win (have never used them) nor was I aware that there could be a SUSE_INSTALL-partition on ntfs (or does this partition belong to WSL?).

And as you do not have an openSUSE rescue system available I won’t be able to help you. Sorry!

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Showing rescue system @susejunky

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@Kailash

I have no idea where this screen comes from.

However what happens when you select “Boot Installed System”?

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What i did not understand