[powerpc]WARN : arch/powerpc/platforms/powernv/smp.c:160

[Sachin Sant]

> On 26-Aug-2019, at 3:42 PM, Sachin Sant <sachinp at linux.vnet.ibm.com> wrote:
> 
>> On 26-Aug-2019, at 8:59 AM, Michael Ellerman <mpe at ellerman.id.au> wrote:
>> 
>> Sachin Sant <sachinp at linux.vnet.ibm.com> writes:
>>> linux-next is currently broken on POWER8 non virtualized. Kernel
>>> fails to reach login prompt with following kernel warning
>>> repeatedly shown during boot.
>> 
>> I don't see it on my test systems.
>> 
>> The backtrace makes it look like you're doing CPU hot_un_plug during
>> boot, which seems a bit odd.
>> 
> There is no explicit hot un plug operation being done. This happens
> during boot.
> 
> For some reason cpu’s are being off lined.  

So this machine was configured as a KVM host. Hence the SMT=1
configuration at boot. Removing QEMU/libvirt packages and unloading
kvm module gets me to SMT 8 config.

Disabling kvm also allows me to boot next kernels without the warning.
The warning is only seen with kvm configured.

Thanks
-Sachin