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.
Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx>
---
drivers/tty/sysrq.c | 2 +-
include/linux/nodemask.h | 10 +++++++++-
mm/oom_kill.c | 2 +-
3 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -355,7 +355,7 @@ static struct sysrq_key_op sysrq_term_op = {
static void moom_callback(struct work_struct *ignored)
{
- out_of_memory(node_zonelist(first_online_node, GFP_KERNEL), GFP_KERNEL,
+ out_of_memory(node_zonelist(first_memory_node, GFP_KERNEL), GFP_KERNEL,
0, NULL, true);
}
diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
--- a/include/linux/nodemask.h
+++ b/include/linux/nodemask.h
@@ -430,7 +430,15 @@ static inline int num_node_state(enum node_states state)
for_each_node_mask((__node), node_states[__state])
#define first_online_node first_node(node_states[N_ONLINE])
-#define next_online_node(nid) next_node((nid), node_states[N_ONLINE])
+#define first_memory_node first_node(node_states[N_MEMORY])
+static inline int next_online_node(int nid)
+{
+ return next_node(nid, node_states[N_ONLINE]);
+}
+static inline int next_memory_node(int nid)
+{
+ return next_node(nid, node_states[N_MEMORY]);
+}
extern int nr_node_ids;
extern int nr_online_nodes;
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -694,7 +694,7 @@ void pagefault_out_of_memory(void)
if (mem_cgroup_oom_synchronize(true))
return;
- zonelist = node_zonelist(first_online_node, GFP_KERNEL);
+ zonelist = node_zonelist(first_memory_node, GFP_KERNEL);
if (try_set_zonelist_oom(zonelist, GFP_KERNEL)) {
out_of_memory(NULL, 0, 0, NULL, false);
clear_zonelist_oom(zonelist, GFP_KERNEL);
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>