diff options
| author | Ming Lei <ming.lei@redhat.com> | 2023-11-17 05:35:22 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-12-20 17:32:35 +0300 |
| commit | a02316281851200b2e77adf42311075413afad72 (patch) | |
| tree | aa08312cd87522b14b514622937d883bc1eba751 | |
| parent | eac54659ff77706569a8419510ca6676b6ff9827 (diff) | |
| download | linux-a02316281851200b2e77adf42311075413afad72.tar.xz | |
blk-throttle: fix lockdep warning of "cgroup_mutex or RCU read lock required!"
[ Upstream commit 27b13e209ddca5979847a1b57890e0372c1edcee ]
Inside blkg_for_each_descendant_pre(), both
css_for_each_descendant_pre() and blkg_lookup() requires RCU read lock,
and either cgroup_assert_mutex_or_rcu_locked() or rcu_read_lock_held()
is called.
Fix the warning by adding rcu read lock.
Reported-by: Changhui Zhong <czhong@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20231117023527.3188627-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | block/blk-throttle.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/block/blk-throttle.c b/block/blk-throttle.c index fcbbe2e45a2b..e52a9632993a 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -1391,6 +1391,7 @@ static void tg_conf_updated(struct throtl_grp *tg, bool global) tg_bps_limit(tg, READ), tg_bps_limit(tg, WRITE), tg_iops_limit(tg, READ), tg_iops_limit(tg, WRITE)); + rcu_read_lock(); /* * Update has_rules[] flags for the updated tg's subtree. A tg is * considered to have rules if either the tg itself or any of its @@ -1418,6 +1419,7 @@ static void tg_conf_updated(struct throtl_grp *tg, bool global) this_tg->latency_target = max(this_tg->latency_target, parent_tg->latency_target); } + rcu_read_unlock(); /* * We're already holding queue_lock and know @tg is valid. Let's |