Write to unrecognized MSR 0x150

[Massimo-B]

Version: 1.7-r1

lscpu |grep name
Model name:                              Intel(R) Core(TM) i7-9700 CPU @ 3.00GHz

uname -r
6.12.31-gentoo-dist

 grep -v "^#" /etc/intel-undervolt.conf

enable yes
undervolt 0 'CPU' -50
undervolt 1 'GPU' -50
undervolt 2 'CPU Cache' -50
undervolt 3 'System Agent' -50
undervolt 4 'Analog I/O' -50
interval 5000
daemon undervolt:once
daemon power
daemon tjoffset

intel-undervolt apply                                                                                                                                                                                1 
CPU (0): Values do not equal
GPU (1): Values do not equal
CPU Cache (2): Values do not equal
System Agent (3): Values do not equal
Analog I/O (4): Values do not equal

In the syslog:

Jun 14 17:04:36 [kernel] [34653.726799] filter_write: 9 callbacks suppressed
Jun 14 17:04:36 [kernel] [34653.726800] msr: Write to unrecognized MSR 0x150 by intel-undervolt (pid: 2335).
Jun 14 17:04:36 [kernel] [34653.726803] msr: See https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/about for details.

What does that mean?
I can't see the msr module loaded:

modprobe msr 

lsmod | grep msr                                                                                                                                                                                SIGINT 
intel_rapl_msr         16384  0
intel_rapl_common      49152  1 intel_rapl_msr

[Washee]

Same problem here. Using Debian Trixie.
On Bookworm everything worked flawlessly.

lscpu | grep name
Model name:                              Intel(R) Core(TM) i7-9700 CPU @ 3.00GHz

uname -r
6.12.43+deb13-amd64

dmesg
[ 1825.845059] msr: Write to unrecognized MSR 0x150 by intel-undervolt (pid: 12642).
[ 1825.845061] msr: See https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/about for details.

It feels like the newer kernel blocks something?
Is there a possibility to fix this somehow?

[Washee]

Ok. I found a solution.

At first I tried editing /etc/default/grub like this:
GRUB_CMDLINE_LINUX_DEFAULT="quiet msr.safe_list=0x150"

After rebooting:

sudo update-grub
sudo reboot

I got:

sudo dmesg  | grep msr
[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-6.12.43+deb13-amd64 root=UUID=68ee110c-ddf1-4444-959c-12f0822eac5d ro quiet msr.safe_list=0x150 
[ 0.020976] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-6.12.43+deb13-amd64 root=UUID=68ee110c-ddf1-4444-959c-12f0822eac5d ro quiet msr.safe_list=0x150 
[ 37.372135] msr: unknown parameter 'safe_list' ignored

Looks like Debian, did not add this "safe_list" parameter. Others did!
I think safe_list is the preferable solution.

For everyone else:
Fortunately we can use GRUB_CMDLINE_LINUX_DEFAULT="quiet msr.allow_writes=on" instead.

@Massimo-B This may help you as well. 👍

[NekoSenseii]

Ok. I found a solution.

At first I tried editing /etc/default/grub like this: GRUB_CMDLINE_LINUX_DEFAULT="quiet msr.safe_list=0x150"

After rebooting:

sudo update-grub
sudo reboot

I got:

sudo dmesg  | grep msr
[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-6.12.43+deb13-amd64 root=UUID=68ee110c-ddf1-4444-959c-12f0822eac5d ro quiet msr.safe_list=0x150 
[ 0.020976] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-6.12.43+deb13-amd64 root=UUID=68ee110c-ddf1-4444-959c-12f0822eac5d ro quiet msr.safe_list=0x150 
[ 37.372135] msr: unknown parameter 'safe_list' ignored

Looks like Debian, did not add this "safe_list" parameter. Others did! I think safe_list is the preferable solution.

For everyone else: Fortunately we can use GRUB_CMDLINE_LINUX_DEFAULT="quiet msr.allow_writes=on" instead.

@Massimo-B This may help you as well. 👍

This is a harmless warning right?