On my Ryzen I’ve 3 Suse Versions - no one is stable:
- 42.2 (standard kernel, somewhat less instable than all other versions) on NVME disk (first prio)
- 42.2 with kernel 4.10.9 (the actual “stable” kernel) on a 4TB disk - it’s nearly not bootable.
- Tumbleweed on an USB3-disk-port (kernel 4.10.9, deactivated per power switch today).
At morning I started (1) as usual and later set it asleep (not Standby - not working -, in “Ruhezustand”).
At weak up boot crashed.
After that only (2) was to be found in the boot options - and not in the boot menu (at <F2>).
Some tries were necessary - after the second try all read only rollup versions were vanished.
The boot menu didn’t even show up any option to boot from NVME (the NVME disk was visible, but not in the boot sequence).
The boot parameters were defect, the saved parameters in NVRAM gone. After some hour I got a start of (2), all data at first glance o.k., but Yast was hanging - no possibility to update the boot menu.
Only the very last option - switch <F12> at boot time to select a boot version - was working, and yast was able to regeneate a boot menu.
(There’s no hint for <F12> at all in the so called “User’s Manual” of the board, only a 1/10 second flash light at boot time!)
As a surprise it was possible to boot the NVME disk using <F12>, and then a setup of the boot menu using Yast.
Now I wanted to look at the efi parameters in a root shell, but it didn’t work as expected. Why?
# efibootmgr
Fatal: Couldn't open either sysfs or procfs directories for accessing EFI variables.
Try 'modprobe efivars' as root.
# modprobe efivars
# efibootmgr -v
Fatal: Couldn't open either sysfs or procfs directories for accessing EFI variables.
Try 'modprobe efivars' as root.
But at next boot after I was able to set all EFI parameters starting from zero and set up the NVRAM disk for boot.
My BIOS info:
# dmidecode -t0
# dmidecode 3.0
Getting SMBIOS data from sysfs.
SMBIOS 3.0 present.
Handle 0x0000, DMI type 0, 24 bytes
BIOS Information
Vendor: American Megatrends Inc.
Version: F2
Release Date: 02/20/2017
Address: 0xF0000
Runtime Size: 64 kB
ROM Size: 16384 kB
Characteristics:
PCI is supported
BIOS is upgradeable
BIOS shadowing is allowed
Boot from CD is supported
Selectable boot is supported
BIOS ROM is socketed
EDD is supported
5.25"/1.2 MB floppy services are supported (int 13h)
3.5"/720 kB floppy services are supported (int 13h)
3.5"/2.88 MB floppy services are supported (int 13h)
Print screen service is supported (int 5h)
Serial services are supported (int 14h)
Printer services are supported (int 17h)
ACPI is supported
USB legacy is supported
BIOS boot specification is supported
Targeted content distribution is supported
UEFI is supported
BIOS Revision: 5.12
Remaining questions: is it possible to give an explanation, what happened?
EFI/BIOS seems to be much more complex than the former BIOS and much more instable and error prone.
Therefore it seems to be necessary to study the mechanism - is there a good source?