Re: [Linux PPC] Disable PREEMPT

["Michal Suchánek" <msuchanek@suse.de>]

On Thu, Sep 10, 2026 at 12:31:09PM +0200, Michal Suchánek wrote:
> On Thu, Sep 10, 2026 at 10:54:07AM +0200, Michal Suchánek wrote:
> > On Mon, Sep 07, 2026 at 01:32:18PM +0200, Christian Zigotzky wrote:
> > > On 07 September 2026 at 10:51 am, Michal Suchánek <msuchanek@suse.de> wrote:
> > > 
> > > There is the obvious question which I did not notice answered in this
> > > thread: Did you set up sysrq and/or kdump and find out where the kernel
> > > is stuck?
> > > 
> > > Thanks
> > > 
> > > Michal
> > > 
> > > - - -
> > > 
> > > I think I need kexec for kdump due to the system freezing after activating of KVM HV. Unfortunately kexec doesn’t work on my machines.
> > > 
> > > Further information: https://github.com/chzigotzky/kernels/releases/tag/Kexec
> > 
> > So there is some bug with kexec initialization on your platform.
> 
> Right, you are missing this part:
> https://github.com/torvalds/linux/blob/50d05c7c76c96b90462f24debacca971d2e86713/arch/powerpc/kexec/core.c#L205
> 
> Maybe it needs to be called from your platform code or something.

Lookig at the code it likely runs always but if your device tree does
not have a /chosen node it does not add the property that kexec needs to
load the kernel. Can you try adding a /chosen node to your device tree?

Thanks

Michal

> 
> Thanks
> 
> Michal
> 
> > 
> > Sysrg for dumping stacks to console might still work.
> > 
> > Thanks
> > 
> > Michal
> > 
>