Arch Linux

Toregi

Member

Registered: 2023-04-03

Posts: 4

acpi=off required to boot (cpu wrongly recognised and X not working)

Edit: I managed to make the new system boot by adding acpi=off to the kernel option.
But now I am hitting several others issues most likely related to acpi=off option.
My compute is using a Nvidia GTX 1050 graphic card and an AMD Ryzen 5 CPU.
When I boot with acpi=off (won't boot otherwise) only 1 out of 8 CPU is detected and Xorg is complaining about ACPI when using startx.
Any ideas on how to fix this acpi issue?

Hello,
I'm hitting a problem after a new installation of Arch Linux.
I have followed the Installation guide (https://wiki.archlinux.org/title/installation_guide) and decided to use GRUB as boot loader (installed as describe in the documentation: https://wiki.archlinux.org/title/GRUB). I use the linux-lts instead of linux kernel.
I have 2 hardrives:
/dev/sda1 = my /home partition
/dev/sdb1 = /boot/EFI
/dev/sdb2 = swap
/dev/sdb3 = /

My /etc/fstab is using UUID with correct values (already check).
After the installation, GRUB is loading well but it got "stuck" after "Loading initial ramdisk ..." message (computer does nothing else).
I have tried to add insmod progress in GRUB config to see what's going on: initramfs gets loaded.
I have check my journalctl after rebooting on my usb stick (and chroot) but no logs so far and also nothing in /run/ .

Does anyone has ideas about what is going on? And how I could get more logs to debug?

Best,

Last edited by Toregi (2023-04-03 13:51:40)

kokoko3k

Member

Registered: 2008-11-14

Posts: 2,394

Re: acpi=off required to boot (cpu wrongly recognised and X not working)

Since the installation didn't hanged, can you install the same kernel of the installation medium (uname -a from it) and try?
https://archive.archlinux.org/packages/l/linux/
Or maybe trying linux-lts?

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Toregi

Member

Registered: 2023-04-03

Posts: 4

Re: acpi=off required to boot (cpu wrongly recognised and X not working)

Thanks for your reply.
The problem was with both latest linux and linux-lts. I said "was" because I managed to find the solution to my problem.
I went with different kernel parameters such as acpi=something (tried different settings) or nomodeset etc.
And after some digging I found the right answer: iommu=off , for some reasons iommu needs to be turned off (I don't know what cause this change because before getting latest kernel version it was working without this option on the computer (before I went with full reinstall (which is not a problem since I have separate partitions with all my configurations)) that was running the same Arch installation since 2018.
Anyway, acpi=off is not needed to make it boot correctly. With iommu=off, all is fine (or looks like at the very least) CPU is recognized as it should (all 8 cores) and graphic cards (nvidia) is working with nouveau driver (haven't tried the nvidia ones but I believe it should work too). Hibernate works the same way as before too.

Do you know why iommu needs to be turned off now?

Lone_Wolf

Forum Moderator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 11,922

Re: acpi=off required to boot (cpu wrongly recognised and X not working)

Needing to change IOMMU settings usually points to a firnware issue, what type & model is your motherboard ?

What is the output of (run with root-rights)

# dmesg | grep DMI:

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Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

(A works at time B)  && (time C > time B ) ≠  (A works at time C)

Toregi

Member

Registered: 2023-04-03

Posts: 4

Re: acpi=off required to boot (cpu wrongly recognised and X not working)

Motherboard is Asus Prime A320M-K and dmesg output gives:
"[   0.0000000] DMI: System manufacturer System Product Name/Prime A320M-K, BIOS 0609 05/15/2017"

I guess the firmware of the motherboard is a bit old (never updated since I bought that motherboard). I must add that I use grub EFI boot.

Lone_Wolf

Forum Moderator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 11,922

Re: acpi=off required to boot (cpu wrongly recognised and X not working)

There have been lots of newer releases, see https://www.asus.com/motherboards-compo … ME-A320M-K

Could you post a journal of  a normal boot with iommu=soft so we can get an idea what functionality you may have lost ?
https://wiki.archlinux.org/title/List_o … n_services for ways to upload the journal somewhere public.

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Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

(A works at time B)  && (time C > time B ) ≠  (A works at time C)

Toregi

Member

Registered: 2023-04-03

Posts: 4

Re: acpi=off required to boot (cpu wrongly recognised and X not working)

Hello,
Thanks for your reply. I have been busy lately that is why I answer so late.
With iommu=soft the computer doesn't boot (stuck at loading initial ramdisk again).

Lone_Wolf

Forum Moderator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 11,922

Re: acpi=off required to boot (cpu wrongly recognised and X not working)

My mistake, it should have been iommu=off .

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Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

(A works at time B)  && (time C > time B ) ≠  (A works at time C)