Re: [Linux PPC] Disable PREEMPT

On 09/20/2026 01:49 PM, Christian Zigotzky wrote:

On 09/18/2026 09:10 AM, Michal Suchánek wrote:

quoted

On Fri, Sep 18, 2026 at 04:39:57AM +0200, Christian Zigotzky wrote:

quoted

On 17/09/26 16:15, Shrikanth Hegde wrote:

quoted

Hi Michal,

quoted

quoted

Give it a try.

I am suspecting both lockup, stack corruptions are secondary
symptoms here.
While recreate, I have different type of traces.

Yes, it does work for the crash I see.

Thanks. Give me sometime to see further on that. Didn't get any time
today.

quoted

However, we hijacked the report
of KVM locking up on FSL Cyrus+, and that is likely a different 
problem
still not addressed.

Ah, that's what you meant. Yes, i still don't know where FSL Cyrus+ is
stuck.

I would need help from FSL Cyrus+ to get some logs or is there a 
way we
can spin of
a QEMU guest of it? We should have the log to start somewhere.

It's difficult to get a log because it freezes and can't write any 
error
messages to the log files. This bug is very old. We had this issue some
years ago but we was able to disable PREEMPT because we don't need it.

I would expect serial console and sysrq could give something, depending
on how much of the kernel is frozen.

Thanks

Michal

Here is a serial log: 
https://github.com/user-attachments/files/32433586/e5500_preempt_putty.log

Another serial log with pcie_ports=compat: 
https://github.com/user-attachments/files/32434487/e5500_preempt_pcie_ports_compat_putty.log

-- 
Sent with BrassMonkey 34.3.2.1 (https://github.com/chzigotzky/Web-Browsers-and-Suites-for-Linux-PPC/releases/tag/BrassMonkey_34.3.2.1)