On memory hot unplug, the kernel removes the node memory type
from the associated memory tier. Use list_del_init instead of
list del such that the same memory type can be added back
to a memory tier on hotplug.
Without this, we get the below warning and return error on
adding memory type to a new memory tier.
[ 33.596095] ------------[ cut here ]------------
[ 33.596099] WARNING: CPU: 3 PID: 667 at mm/memory-tiers.c:115 set_node_memory_tier+0xd6/0x2e0
[ 33.596109] Modules linked in: kmem
...
[ 33.596126] RIP: 0010:set_node_memory_tier+0xd6/0x2e0
....
[ 33.596196] memtier_hotplug_callback+0x48/0x68
[ 33.596204] blocking_notifier_call_chain+0x80/0xc0
[ 33.596211] online_pages+0x25e/0x280
[ 33.596218] memory_block_change_state+0x176/0x1f0
[ 33.596225] memory_subsys_online+0x37/0x40
[ 33.596230] online_store+0x9b/0x130
[ 33.596236] kernfs_fop_write_iter+0x128/0x1b0
[ 33.596242] vfs_write+0x24b/0x2c0
[ 33.596249] ksys_write+0x74/0xe0
[ 33.596254] do_syscall_64+0x43/0x90
[ 33.596259] entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fixes: mm/demotion: Add hotplug callbacks to handle new numa node onlined
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
---
mm/memory-tiers.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c
index a20795bb0e07..ba844fe9cc8c 100644
--- a/mm/memory-tiers.c
+++ b/mm/memory-tiers.c
@@ -451,7 +451,7 @@ static bool clear_node_memory_tier(int node)
memtype = node_memory_types[node];
node_clear(node, memtype->nodes);
if (nodes_empty(memtype->nodes)) {
- list_del(&memtype->tier_sibiling);
+ list_del_init(&memtype->tier_sibiling);
if (list_empty(&memtier->memory_types))
destroy_memory_tier(memtier);
}
--
2.37.2
