Re: [PATCH 4.19 226/321] mm/hotplug: invalid PFNs from pfn_to_online_page()

[Greg Kroah-Hartman]

On Thu, Dec 05, 2019 at 11:14:52PM +0100, Pavel Machek wrote:
> Hi!
> 
> > This is due to the commit 9f1eb38e0e11 ("mm, kmemleak: little
> > optimization while scanning") starts to use pfn_to_online_page() instead
> > of pfn_valid().  However, in the CONFIG_MEMORY_HOTPLUG=y case,
> > pfn_to_online_page() does not call memblock_is_map_memory() while
> > pfn_valid() does.
> ...
> > Fixes: 9f1eb38e0e11 ("mm, kmemleak: little optimization while scanning")
> 
> Commit 9f1eb38e0e11 does not seem to be in v4.19-stable tree. Is this
> commit still neccessary/good idea?

Good catch.

Sasha, should this be reverted?  How did your scripts pick this?

thanks,

greg k-h