[PATCH v3 2/2] powerpc/mm/radix: Free PUD table when freeing pagetable

[Bharata B Rao]

On Tue, Jul 30, 2019 at 02:37:16PM -0500, Reza Arbab wrote:
> On Fri, Jul 26, 2019 at 10:34:40AM +0530, Bharata B Rao wrote:
> > remove_pagetable() isn't freeing PUD table. This causes memory
> > leak during memory unplug. Fix this.
> 
> On x86, this is intentional. See
> 
> af2cf278ef4f ("x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()")
> 98fe3633c5a4 ("x86/mm/hotplug: Fix BUG_ON() after hot-remove by not freeing PUD")
> 
> Does their reasoning apply to powerpc as well?

x86 seems to maintain some global pgd list that needs to sync'ed up
when PGD entry is freed. Since powerpc doesn't have that equivalent
I don't see that reasoning applying here. However if there is more
to it than just this, then I am not sure.

Regards,
Bharata.