Merge branch 'for-4.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup fixes from Tejun Heo:
 "Two commits to fix the following subtle cgroup2 behavior bugs:

   - cpu.max was rejecting config when it shouldn't

   - thread mode enable was allowed when it shouldn't"

* 'for-4.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix rule checking for threaded mode switching
  sched, cgroup: Don't reject lower cpu.max on ancestors
This commit is contained in:
Linus Torvalds 2018-03-19 15:39:02 -07:00
commit 1b5f3ba415
2 changed files with 20 additions and 5 deletions

View File

@ -3183,6 +3183,16 @@ static int cgroup_enable_threaded(struct cgroup *cgrp)
if (cgroup_is_threaded(cgrp))
return 0;
/*
* If @cgroup is populated or has domain controllers enabled, it
* can't be switched. While the below cgroup_can_be_thread_root()
* test can catch the same conditions, that's only when @parent is
* not mixable, so let's check it explicitly.
*/
if (cgroup_is_populated(cgrp) ||
cgrp->subtree_control & ~cgrp_dfl_threaded_ss_mask)
return -EOPNOTSUPP;
/* we're joining the parent's domain, ensure its validity */
if (!cgroup_is_valid_domain(dom_cgrp) ||
!cgroup_can_be_thread_root(dom_cgrp))

View File

@ -6683,13 +6683,18 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
parent_quota = parent_b->hierarchical_quota;
/*
* Ensure max(child_quota) <= parent_quota, inherit when no
* Ensure max(child_quota) <= parent_quota. On cgroup2,
* always take the min. On cgroup1, only inherit when no
* limit is set:
*/
if (quota == RUNTIME_INF)
quota = parent_quota;
else if (parent_quota != RUNTIME_INF && quota > parent_quota)
return -EINVAL;
if (cgroup_subsys_on_dfl(cpu_cgrp_subsys)) {
quota = min(quota, parent_quota);
} else {
if (quota == RUNTIME_INF)
quota = parent_quota;
else if (parent_quota != RUNTIME_INF && quota > parent_quota)
return -EINVAL;
}
}
cfs_b->hierarchical_quota = quota;