Commit 54504e97 authored by Tejun Heo's avatar Tejun Heo
Browse files

cgroup: cgroup_idr_lock should be bh 



cgroup_idr_remove() can be invoked from bh leading to lockdep
detecting possible AA deadlock (IN_BH/ON_BH).  Make the lock bh-safe.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Acked-by: default avatarLi Zefan <lizefan@huawei.com>
parent 0cee8b77

kernel/cgroup.c

+6 −6
Original line number Diff line number Diff line
@@ -203,9 +203,9 @@ static int cgroup_idr_alloc(struct idr *idr, void *ptr, int start, int end, 
	int ret;



	idr_preload(gfp_mask);

	spin_lock(&cgroup_idr_lock);

	spin_lock_bh(&cgroup_idr_lock);

	ret = idr_alloc(idr, ptr, start, end, gfp_mask);

	spin_unlock(&cgroup_idr_lock);

	spin_unlock_bh(&cgroup_idr_lock);

	idr_preload_end();

	return ret;

}
@@ -214,17 +214,17 @@ static void *cgroup_idr_replace(struct idr *idr, void *ptr, int id) 
{

	void *ret;



	spin_lock(&cgroup_idr_lock);

	spin_lock_bh(&cgroup_idr_lock);

	ret = idr_replace(idr, ptr, id);

	spin_unlock(&cgroup_idr_lock);

	spin_unlock_bh(&cgroup_idr_lock);

	return ret;

}



static void cgroup_idr_remove(struct idr *idr, int id)

{

	spin_lock(&cgroup_idr_lock);

	spin_lock_bh(&cgroup_idr_lock);

	idr_remove(idr, id);

	spin_unlock(&cgroup_idr_lock);

	spin_unlock_bh(&cgroup_idr_lock);

}



/**