Odd kernel panic behavior

[oshunluvr]

I'm having rather random kernel crashes at boot up lately. Not always, just sometimes.

Sequence of events:

Update system and install new kernel.
Reboot - kernel panic.
Reboot to previous kernel.
Reinstall new kernel.
Reboot - works fine.

Twice, I've had to restore a previous day's snapshot because for some unknown reason none of the three kernels I keep will boot, but subsequent updates and they work fine.

This occurs only with kernel updates and not every time I update. Also, re-installing the failing kernel usually works, but not 4.13-0.36, it has never booted even after re-install. This morning, the two older kernels - 4.13.0-33 and -35 both kernel panicked on reboot so I had to restore the snapshot. I'm about to reboot again after re-running the update.

I guess my questions is what could cause this and where do I start looking?

BTW, I would suspect hardware but this was happening of my previous motherboard also and when I get stuck and have to restore a snapshot, I boot to Manjaro and it works every time. I'll take a pic of the kernel fault message next time it happens.

[oshunluvr]

I restored a snapshot, booted to 4.13.0-35, re-ran update, re-installed 4.13.0-36.

On reboot, -36 and -36 crashed but -33 booted. Previously, -33 crashed also.

This message from the boot output seems to be relevant:

VFS: Cannot open root device "UUID...." or unknown-block(0,0): error -6

[oshunluvr]

After snapshot restore, -33 will boot. No others. I tried rebuilding initramfs for -36 but still crashed. I did noticed the crash messages for -36 were different for -35. It must be a kernel issue.

[oshunluvr]

Further info; I went through several reboots. No kernel would boot. On a hunch, I rebooted -33 twice in a row. The second time it booted.

[oshunluvr]

Looks like it's a GRUB vs. File system issue. On a hunch, I removed the "hints" from grub. So instead of this:

search --no-floppy --fs-uuid --set=root --hint-bios=hd3,gpt3 --hint-efi=hd3,gpt3 --hint-baremetal=ahci3,gpt3  8f0c1661-4e84-4512-b875-23bcfd5be1d8

I booted with this:

search --no-floppy --fs-uuid --set=root 8f0c1661-4e84-4512-b875-23bcfd5be1d8

and it booted right up.

[GreyGeek]

So, what feature sets are missing because you removed:

--hint-bios=hd3,gpt3 --hint-efi=hd3,gpt3 --hint-baremetal=ahci3,gpt3

and let it do its own search thing?


If you put your first search in an IF and the second in its ELSE would that automatically boot using the 2nd if the first failed?

[oshunluvr]

I don't know, but there's something amiss. Manjaro boots, but the kernel is different. Getting ready to take my bride on vacation so I won't be figuring this out until we get back