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| author | Chengming Zhou <zhouchengming@bytedance.com> | 2023-09-29 16:16:07 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-10-06 13:18:19 +0200 |
| commit | c8bc44936f2c502429be4ae7940cbaced3b6e565 (patch) | |
| tree | 063dc8131e1674dc7525cd192899e51dfc5530a2 | |
| parent | ce6b88a5853d69a3d023c219e50f708e1d30b0e3 (diff) | |
| download | linux-c8bc44936f2c502429be4ae7940cbaced3b6e565.tar.gz linux-c8bc44936f2c502429be4ae7940cbaced3b6e565.tar.bz2 linux-c8bc44936f2c502429be4ae7940cbaced3b6e565.zip | |
cgroup: Fix suspicious rcu_dereference_check() usage warning
commit f2aa197e4794bf4c2c0c9570684f86e6fa103e8b upstream.
task_css_set_check() will use rcu_dereference_check() to check for
rcu_read_lock_held() on the read-side, which is not true after commit
dc6e0818bc9a ("sched/cpuacct: Optimize away RCU read lock"). This
commit drop explicit rcu_read_lock(), change to RCU-sched read-side
critical section. So fix the RCU warning by adding check for
rcu_read_lock_sched_held().
Fixes: dc6e0818bc9a ("sched/cpuacct: Optimize away RCU read lock")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Reported-by: syzbot+16e3f2c77e7c5a0113f9@syzkaller.appspotmail.com
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Tested-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20220305034103.57123-1-zhouchengming@bytedance.com
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | include/linux/cgroup.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index f425389ce4bb..0d97d1cf660f 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -451,6 +451,7 @@ extern struct mutex cgroup_mutex; extern spinlock_t css_set_lock; #define task_css_set_check(task, __c) \ rcu_dereference_check((task)->cgroups, \ + rcu_read_lock_sched_held() || \ lockdep_is_held(&cgroup_mutex) || \ lockdep_is_held(&css_set_lock) || \ ((task)->flags & PF_EXITING) || (__c)) |