Oldhabbits
Active Member
No solutions found thus far, still using the power switch…
cheers,
Eddy
cheers,
Eddy
Linux on iMac reboots instead of shutdown
I have seen issues periodically on fedora that causes the inability to restart and also to cause restart instead of shutdown. The problem is indeed ACPI related and has to be fixed in the kernel with an update. Which may never come if it is not a known reported bug.
The problem when I see it seems to come from the watchdog which is meant to reboot the system if it is locked up or experiences a severe problem. So the watchdog is most likely the culprit here.
what follows is my notes on this.
================ nmi watchdog ====================================
cat /proc/sys/kernel/nmi_watchdog ---- shows status, 1= on 0= off
sudo sysctl kernel.nmi_watchdog=x ---- replace x with 1 or 0, changes value til restart which will allow you to test if this is the issue
/etc/sysctl.conf enter line kernel.nmi_watchdog=x --- makes it permanent. Default is on
The problem when I see it seems to come from the watchdog which is meant to reboot the system if it is locked up or experiences a severe problem. So the watchdog is most likely the culprit here.
what follows is my notes on this.
================ nmi watchdog ====================================
cat /proc/sys/kernel/nmi_watchdog ---- shows status, 1= on 0= off
sudo sysctl kernel.nmi_watchdog=x ---- replace x with 1 or 0, changes value til restart which will allow you to test if this is the issue
/etc/sysctl.conf enter line kernel.nmi_watchdog=x --- makes it permanent. Default is on
Oldhabbits
Active Member
Just tried your idea, but it has no effect on my imac 2016. Still needed the power button as usual… Thanks anyway !
Cheers,
Eddy
Hi!
Just wanted to let everyone know that I just submitted a bug report for this problem on the Linux Kernel Bugzilla:
219185 – System reboots after shutdown or sleep
If anyone is interested in helping with feedback and testing, feel free to do so.
Hope for the best!
Just wanted to let everyone know that I just submitted a bug report for this problem on the Linux Kernel Bugzilla:
219185 – System reboots after shutdown or sleep
If anyone is interested in helping with feedback and testing, feel free to do so.
Hope for the best!
Oldhabbits
Active Member
I have the same problem with my imac, only in macos or windows it will shutdown properly…
Long ago, I read an article about this. It is an certain register in the cpu that should receive an impuls to shutdown completly. Macos does that, Windows too but our linux kernel does not. Apple did not connect a certain cpu pin on their motherbords, needed for sending that signal like Intel had foreseen this for other motherbords. Apple’s macos is sending an other instructionset to accomplish the same effect, but Linux can not do the same thing to keep itself compatible with other brands of computers.
But now you know why we have to press that button !
Greetz, Eddy
Long ago, I read an article about this. It is an certain register in the cpu that should receive an impuls to shutdown completly. Macos does that, Windows too but our linux kernel does not. Apple did not connect a certain cpu pin on their motherbords, needed for sending that signal like Intel had foreseen this for other motherbords. Apple’s macos is sending an other instructionset to accomplish the same effect, but Linux can not do the same thing to keep itself compatible with other brands of computers.
But now you know why we have to press that button !
Greetz, Eddy
Last edited:
mrcrossroads
Well-Known Member
I had Mint running on a 2013 iMac and didn't have the issue.
You might try using /usr/sbin/poweroff which is a symlink to /usr/bin/systemctl. When called as poweroff it should shut down the system and leave it that way. I either use poweroff or reboot.
Signed,
Matthew Campbell
Signed,
Matthew Campbell
