Paul E. McKenney wrote: > On Thu, Apr 22, 2010 at 05:32:28PM +0800, Li Zefan wrote: >> with CONFIG_PROVE_RCU=y, a warning can be triggered: >> >> # mount -t cgroup -o blkio xxx /mnt >> # mkdir /mnt/subgroup >> >> ... >> kernel/cgroup.c:4442 invoked rcu_dereference_check() without protection! >> ... >> >> To fix this, we avoid caling css_depth() here, which is a bit simpler >> than the original code. > > Queued for 2.6.34, thank you! > Seems neither you nor Jens queued this patch... > Thanx, Paul > >> Signed-off-by: Li Zefan <lizf@xxxxxxxxxxxxxx> >> --- >> block/blk-cgroup.c | 8 ++++---- >> 1 files changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c >> index 5fe03de..2cc682b 100644 >> --- a/block/blk-cgroup.c >> +++ b/block/blk-cgroup.c >> @@ -286,16 +286,16 @@ done: >> static struct cgroup_subsys_state * >> blkiocg_create(struct cgroup_subsys *subsys, struct cgroup *cgroup) >> { >> - struct blkio_cgroup *blkcg, *parent_blkcg; >> + struct blkio_cgroup *blkcg; >> + struct cgroup *parent = cgroup->parent; >> >> - if (!cgroup->parent) { >> + if (!parent) { >> blkcg = &blkio_root_cgroup; >> goto done; >> } >> >> /* Currently we do not support hierarchy deeper than two level (0,1) */ >> - parent_blkcg = cgroup_to_blkio_cgroup(cgroup->parent); >> - if (css_depth(&parent_blkcg->css) > 0) >> + if (parent != cgroup->top_cgroup) >> return ERR_PTR(-EINVAL); >> >> blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL); >> -- >> 1.6.3 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> Please read the FAQ at http://www.tux.org/lkml/ > > _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers