Re: [RFC PATCH 3/3] powerpc/pseries/vas: Use migration_in_progress to disable DLPAR

[Haren Myneni <haren@linux.ibm.com>]

On Fri, 2022-01-14 at 11:59 -0600, Nathan Lynch wrote:
> Haren Myneni <haren@linux.ibm.com> writes:
> 
> > Before migration starts, all secondary CPUs will be offline which
> > can invoke VAS DLPAR event.
> 
> I don't understand this statement, so I can't evaluate the patch. The
> current LPM implementation does not offline any CPUs.

Thanks for your comment. My mistake..

VAS notifier with of_reconfig_notifier_register() is called during
migration for other events. VAS notifier has a bug (
https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-December/238333.html
) and will fix it:

if ((action == OF_RECONFIG_ATTACH_NODE) ||
        (action == OF_RECONFIG_DETACH_NODE))
        intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
&len);

As the current LPM notifier does not freeze the system, thought of
ignoring DLPAR CPU hotplug event with this migration_in_progress flag. 

I will fix this as well and repost DLPAR NXGZIP series. 

Thanks
Haren