diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 98e644b0a532..58e02e9aa970 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -1309,18 +1309,17 @@ static umode_t cgroup_file_mode(const struct cftype *cft) /** * cgroup_calc_subtree_ss_mask - calculate subtree_ss_mask - * @cgrp: the target cgroup * @subtree_control: the new subtree_control mask to consider + * @this_ss_mask: available subsystems * * On the default hierarchy, a subsystem may request other subsystems to be * enabled together through its ->depends_on mask. In such cases, more * subsystems than specified in "cgroup.subtree_control" may be enabled. * * This function calculates which subsystems need to be enabled if - * @subtree_control is to be applied to @cgrp. The returned mask is always - * a superset of @subtree_control and follows the usual hierarchy rules. + * @subtree_control is to be applied while restricted to @this_ss_mask. */ -static u16 cgroup_calc_subtree_ss_mask(struct cgroup *cgrp, u16 subtree_control) +static u16 cgroup_calc_subtree_ss_mask(u16 subtree_control, u16 this_ss_mask) { u16 cur_ss_mask = subtree_control; struct cgroup_subsys *ss; @@ -1328,9 +1327,6 @@ static u16 cgroup_calc_subtree_ss_mask(struct cgroup *cgrp, u16 subtree_control) lockdep_assert_held(&cgroup_mutex); - if (!cgroup_on_dfl(cgrp)) - return cur_ss_mask; - while (true) { u16 new_ss_mask = cur_ss_mask; @@ -1343,7 +1339,7 @@ static u16 cgroup_calc_subtree_ss_mask(struct cgroup *cgrp, u16 subtree_control) * happen only if some depended-upon subsystems were bound * to non-default hierarchies. */ - new_ss_mask &= cgroup_ss_mask(cgrp); + new_ss_mask &= this_ss_mask; if (new_ss_mask == cur_ss_mask) break; @@ -3012,8 +3008,9 @@ static void cgroup_propagate_control(struct cgroup *cgrp) cgroup_for_each_live_descendant_pre(dsct, d_css, cgrp) { dsct->subtree_control &= cgroup_control(dsct); - dsct->subtree_ss_mask = cgroup_calc_subtree_ss_mask(dsct, - dsct->subtree_control); + dsct->subtree_ss_mask = + cgroup_calc_subtree_ss_mask(dsct->subtree_control, + cgroup_ss_mask(dsct)); } }