Bug 1226126

Summary:	[Build :34123:kernel-default] system can't snapper rollback to previous kernel
Product:	[openSUSE] PUBLIC SUSE Linux Enterprise Server 15 SP6	Reporter:	Jozef Pupava <jpupava>
Component:	Kernel	Assignee:	Kernel Bugs <kernel-bugs>
Status:	RESOLVED INVALID	QA Contact:
Severity:	Critical
Priority:	P1 - Urgent	CC:	jcheung, meissner, osalvador, rfrohl, richard.fan, tiwai
Version:	unspecified
Target Milestone:	---
Hardware:	x86-64
OS:	Other
URL:	https://openqa.suse.de/tests/14554983/modules/update_install/steps/343
Whiteboard:
Found By:	openQA	Services Priority:
Business Priority:		Blocker:	Yes
Marketing QA Status:	---	IT Deployment:	---
Attachments:	dmesg dumpe2fs /dev/vda1 or /dev/disk/by-path/pci-0000:00:09.0-part1

Description Jozef Pupava 2024-06-10 07:04:17 UTC

Created attachment 875393 [details]
dmesg

## Observation

With kernel update https://build.suse.de/request/show/333406
System does boot, but when running snapper rollback to snapshot with previous kernel,
system will end in emergency mode.

Jun 07 18:03:46.967431 susetest mount[539]: mount: /boot: unknown filesystem type 'ext2'.
Jun 07 18:03:46.967431 susetest mount[539]:        dmesg(1) may have more information after failed mount system call.
Jun 07 18:03:46.967622 susetest systemd[1]: boot.mount: Mount process exited, code=exited, status=32/n/a
Jun 07 18:03:46.967627 susetest systemd[1]: boot.mount: Failed with result 'exit-code'.

https://openqa.suse.de/tests/14554983/modules/update_install/steps/343


## Reproducible

Fails since (at least) Build [:34123:dtb-armv7l](https://openqa.suse.de/tests/14554963)


## Expected result

Last good: [:34204:linuxrc](https://openqa.suse.de/tests/14554692) (or more recent)


## Further details

Always latest result in this scenario: [latest](https://openqa.suse.de/tests/latest?arch=x86_64&distri=sle&flavor=Server-DVD-Incidents-Install&machine=64bit&test=qam-incidentinstall&version=15-SP6)

Comment 1 Jozef Pupava 2024-06-10 07:06:32 UTC

Same issue on x86_64 15-SP5 with kernel update https://build.suse.de/request/show/333407

Comment 2 Jozef Pupava 2024-06-10 07:28:36 UTC

Created attachment 875395 [details]
dumpe2fs /dev/vda1 or /dev/disk/by-path/pci-0000:00:09.0-part1

Comment 3 Jozef Pupava 2024-06-11 14:12:58 UTC

A rollback of the boot loader is not possible, since all “stages” of the boot loader must fit together. This cannot be guaranteed when doing rollbacks of /boot. [1]

[1] https://doc.opensuse.org/documentation/leap/archive/15.0/reference/html/book.opensuse.reference/cha.snapper.html#sec.snapper.limits.snapshot-boot.grub