Re: [PATCH v1 1/3] mm: fix uninitialized memmaps on a partially populated last section

[Daniel Jordan]

On Tue, Dec 10, 2019 at 11:11:03AM +0100, David Hildenbrand wrote:
> Some things that might be relevant from my config.
> 
> # CONFIG_PAGE_POISONING is not set
> CONFIG_DEFERRED_STRUCT_PAGE_INIT=y
> CONFIG_SPARSEMEM_EXTREME=y
> CONFIG_SPARSEMEM_VMEMMAP_ENABLE=y
> CONFIG_SPARSEMEM_VMEMMAP=y
> CONFIG_HAVE_MEMBLOCK_NODE_MAP=y
> CONFIG_MEMORY_HOTPLUG=y
> CONFIG_MEMORY_HOTPLUG_SPARSE=y
> CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE=y

Thanks for all that.  After some poking around, turns out enabling DEBUG_VM
with its page poisoning let me hit it right away, which makes me wonder how
often someone would see this without it.

Anyway, fix looks good to me.

Tested-by: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx>