I’m having similar issue. Every night HA just stops working, dmesg indicates rcu_preempt error. This was happening before, but in 2025 it is a nightly occurrence.
I don’t have hyper-v, my home assistant runs in ubuntu linux in libvirt environment. Allocating it more CPUs and RAM did not help a single bit.
Yesterday I tried to disablr rcu_preempt using:
echo 1 > /sys/module/rcupdate/parameters/rcu_cpu_stall_suppress
this got rid of rcu_preempt, but home assistant hanged anyway.
Same for me. l disabled Hyper-V but every night i see this error and need to restart. Help!
I think I have it fixed by pinning CPU cores to a single processor. My host is 2-CPU, and what I think might have been happening is that cores allocated were on different CPUs, which might have been causing issues. Not sure. Machine was crashing every night. After CPUs were pinned, I no longer see crashes, and it’s been more than a week.
@galets , could you please elaborate on exactly what you did here?
I have been running HAOS in VirtulBox on Windows 11 without any issues at all up until 2 days ago when it started crashing with the same error.
I suspect it is a change in the latest HAOS update, but I am not sure what exactly could be the problem.
Thanks
Same Problem here.
HA on latest VMware Workstation.
Guest OS is Windows 11, Gen 12 Intel CPU
Docker also running with other tasks
Out of nothing, same problem started a few days ago
Tried Solution ( Answer 4) on this thread.
HA crashed again tonight
Now reduced the amount of CPU Cores from 4 to 1
Lets see if it helps
HA responsivness with one core seems good
Update 24h: later.
Combination of “Answer Nr. 4” + Reductiion HA to “one core” did the job for the moment.
And … I think I remember I did update HA (core) some hours before the troubles occured. Maybe the current HA Version produces (new) troubles.
OS Version: 14.2
Home Assistant Core: 2025.2.4
I’ve encountered a similar problem where Home Assistant was crashing randomly after updating to version 2025.2.4. After some investigation, I found that reducing the number of CPU cores from 4 to 1 seemed to stabilize the system for now. The performance with a single core is still acceptable, and Home Assistant responsiveness has improved.
I believe the issue may be related to CPU resource management in virtualized environments (I’m using VMware Workstation with Windows 11 as the guest OS). I’m not sure if the latest HA update (core 2025.2.4) introduced new problems that cause instability with multiple CPU cores.
Just wanted to share in case anyone else is experiencing the same issue. Let me know if anyone has similar experiences or if there are other solutions to fix the problem with multiple CPU cores.
Hello,
I also experienced the same problems with my CPU
It started a few days ago without anything being modified on my system.
I host home Assistant on Virtual Box.
I disabled Hyper V and switched from 4 to 1 core.
I still had the problem and went to 2 Cores
And now it works fine.
Just wanted to add two data points here (since I have also been seeing these RCU_preempt detected stall" messages with Linux VMs).
It’s not something specific to Home Assistant. I’m running Ubuntu VMs and they do it, seems like on them it either happens at bootup or not at all. For some reason it doesn’t seem to happen on one with OpenSUSE or Mint, but that may be a coincidence I suppose since (as michaelkrtikos says this is a CPU time sync related issue so they may just ‘exercise’ the CPU cores differently at bootup. Could be different kernel options I suppose; or the OpenSuse etc. do all have different kernel versions, so maybe this is a ‘bug’ in some kernel series but not others?
I’m using a Linux host! So this is not some deal with HyperV specifically, or some other Windows-ly issue. Since it’s essentially a race condition, some random setting change on your host may make it clear up.
I’m probably going to go around turning my stuff down to 1 core. I’m not running anything too CPU-intensive in my VMs.