We got report that setting cpuset.mems failed when the nodemask
contains a newly onlined memory node (not enumerated during boot)
for cgroup v2, while the binding succeeded for cgroup v1.
The root cause is, for cgroup v2, when a new memory node is onlined,
top_cpuset's 'mem_allowed' is not updated with the new nodemask of
memory nodes, and the following setting memory nodemask will fail,
if the nodemask contains a new node.
Fix it by updating top_cpuset.mems_allowed right after the
new memory node is onlined, just like v1.
Signed-off-by: Feng Tang <feng.tang@xxxxxxxxx>
---
Very likely I missed some details here, but it looks strange that
the top_cpuset.mem_allowed is not updatd even after we onlined
several memory nodes after boot.
kernel/cgroup/cpuset.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 9390bfd9f1cd..b97caaf16374 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -3314,8 +3314,7 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
/* synchronize mems_allowed to N_MEMORY */
if (mems_updated) {
spin_lock_irq(&callback_lock);
- if (!on_dfl)
- top_cpuset.mems_allowed = new_mems;
+ top_cpuset.mems_allowed = new_mems;
top_cpuset.effective_mems = new_mems;
spin_unlock_irq(&callback_lock);
update_tasks_nodemask(&top_cpuset);
--
2.27.0
