Genkernel and resuming

Message

NTwoO · Post by **NTwoO** » Tue Oct 15, 2019 8:03 pm

Hi, I've been looking into hibernation and resuming. The hibernation seems to roll quite smoothly, but resuming is not quite the smooth ride I expected.

For the first time I decided to roll with genkernel with my new machine. It does have its advantages and I do roll with a custom kernel config, so not the bulky standard issue weaponry. The one thing I can't figure out is how to pass the "real_resume" to the initramfs scripting. Can anyone help there? I added a REAL_RESUME=<swaplocation> to /etc/genkernel.conf just below the commented REAL_ROOT=<> field, but to no avail. providing it in the commandline didn't roll either.

eccerr0r · Post by **eccerr0r** » Tue Oct 15, 2019 10:10 pm

I think sys-kernel/genkernel-3.5.3.3 initramfs has a bug with resume... may need to try it without it.

NTwoO · Post by **NTwoO** » Wed Oct 16, 2019 4:05 am

I'm rolling with 4.0.0

Marlo · Post by **Marlo** » Wed Oct 16, 2019 9:21 am

"man genkernel" is your friend

man genkernel wrote: real_resume=<...>, resume=<...>, noresume
noresume disables any default resume parameters. resume and real_resume specify a device via LABEL or UUID to
use for loading a SWSUSP resume image.

NTwoO · Post by **NTwoO** » Fri Oct 18, 2019 6:28 am

How does one pass these arguments to genkernel? It gives errors in the command line. Should I add an option in the command line? There is no example in the genkernel wiki page

Marlo · Post by **Marlo** » Fri Oct 18, 2019 12:39 pm

NTwoO,

man genkernel contains several chapters. There are:

ACTIONS
OPTIONS
RAMDISK OPTIONS
HOOKS
Netbooting
REPORTING
BUGS
AUTHORS

The full text explaining "RAMDISK OPTIONS" is:

Code: Select all

"RAMDISK OPTIONS
       The following options can be passed as kernel parameters from the bootloader, which the ramdisk scripts would recognize."

The developers give here a hint for another configfile. This means, it must in /etc/default/grub an entry into it.

But honestly, it's a bit confusing.
Basically, the following should be noted:

1. There are boot parameters for the kernel
2. There are boot-parameters for the initramfs.

And both parameters are in /etc/default/grub in the
GRUB_CMDLINE_LINUX_DEFAULT=
or
GRUB_CMDLINE_LINUX=
to hand over.
So "root=/dev/xxx" is for the kernel
and "real_root=xxx=xxx" for the initramfs.
The common language only speaks of kernel parameters. This always means: CMDLINE in /etc/default/grub.

But note:
"real_resume =" must be set with the LABEL or UUID.

I have for example:

GRUB_CMDLINE_LINUX_DEFAULT="real_resume=UUID=80512d9a-88c9-48f9-85b4-60ac7eacb2"

Read on here:
viewtopic-p-6869968.html
viewtopic-t-1084166-start-0.html
https://wiki.gentoo.org/wiki/GRUB#Using_LABEL_or_UUID

Ma

NTwoO · Post by **NTwoO** » Sat Oct 19, 2019 11:31 am

Thanks! So these are not intended in the commandline of genkernel. If I get things working and understand it better, I'll look into updatiing the genkernel wiki.

EDIT: But the kernel can also eat the (PART)UUID labels according to the docs? So the resume can also be a PARTUUID?

eccerr0r · Post by **eccerr0r** » Sat Oct 19, 2019 4:39 pm

The initramfs should be able to understand LABEL= or UUID=, but the kernel itself only supports /dev/devices or PARTUUID= at least for rootfs.

I would imagine that the kernel should accept PARTUUID by itself as well for resume.

NTwoO · Post by **NTwoO** » Sat Oct 19, 2019 8:35 pm

OK, thanks for the tip. It might explain why things were not working as it should yet

eccerr0r · Post by **eccerr0r** » Sat Oct 19, 2019 10:11 pm

Not sure if genkernel 4.0 initramfs works for resume yet either, anyone know?

Can you boot without initramfs or are you depending on some feature in it?

NTwoO · Post by **NTwoO** » Sun Oct 20, 2019 6:11 am

Yesterday evening I checked the initrd img of genkernel to see if there might be a clue why things are still failing. It only contains the early intel microcode. That I can add to the kernel code and skip initrd.

NTwoO · Post by **NTwoO** » Sun Oct 27, 2019 8:56 pm

The kernel is now starting without the initramfs. root and resume is set to the PARTUUIDs. The progress dialogue during suspend shows the indication that the s2disk is working well. During resume nothing is mentioned. How can I debug the resume trajectory?

Whissi · Post by **Whissi** » Mon Oct 28, 2019 12:51 am

eccerr0r wrote:Not sure if genkernel 4.0 initramfs works for resume yet either, anyone know?

Works fine for me.

NTwoO · Post by **NTwoO** » Tue Oct 29, 2019 8:31 pm

OK, so the current 4.0 genkernel should work. That could still have some config pointers on (PART)UUID setitings for (real_)resume/root sprinkled through various configs and such through etc and other places.