[PATCH] cgroup: properly init u64_stats

From: Lucas Stach
Date: Tue Nov 28 2017 - 07:59:37 EST


Lockdep complains that the stats update is trying to register a non-static
key. This is because u64_stats are using a seqlock on 32bit arches, which
needs to be initialized before usage.

Fixes: 041cd640b2f3 (cgroup: Implement cgroup2 basic CPU usage accounting)
Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
---
kernel/cgroup/stat.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/kernel/cgroup/stat.c b/kernel/cgroup/stat.c
index 133b465691d6..1e111dd455c4 100644
--- a/kernel/cgroup/stat.c
+++ b/kernel/cgroup/stat.c
@@ -296,8 +296,12 @@ int cgroup_stat_init(struct cgroup *cgrp)
}

/* ->updated_children list is self terminated */
- for_each_possible_cpu(cpu)
- cgroup_cpu_stat(cgrp, cpu)->updated_children = cgrp;
+ for_each_possible_cpu(cpu) {
+ struct cgroup_cpu_stat *cstat = cgroup_cpu_stat(cgrp, cpu);
+
+ cstat->updated_children = cgrp;
+ u64_stats_init(&cstat->sync);
+ }

prev_cputime_init(&cgrp->stat.prev_cputime);

--
2.11.0