With memoryless node support being worked on, it's possible that for
optimizations that a node may not have a non-NULL zonelist. When
CONFIG_NUMA is enabled and node 0 is memoryless, this means the zonelist
for first_online_node may become NULL.
The oom killer requires a zonelist that includes all memory zones for
the sysrq trigger and pagefault out of memory handler.
Ensure that a non-NULL zonelist is always passed to the oom killer.
[akpm@linux-foundation.org: fix non-numa build]
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8d060bf490