cpuset: make sure new tasks conform to the current config of the cpuset

A new task inherits cpus_allowed and mems_allowed masks from its parent,
but if someone changes cpuset's config by writing to cpuset.cpus/cpuset.mems
before this new task is inserted into the cgroup's task list, the new task
won't be updated accordingly.

Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
This commit is contained in:
Zefan Li 2016-08-09 11:25:01 +08:00 committed by Tejun Heo
parent 29b4817d40
commit 06f4e94898

View File

@ -2069,6 +2069,20 @@ static void cpuset_bind(struct cgroup_subsys_state *root_css)
mutex_unlock(&cpuset_mutex);
}
/*
* Make sure the new task conform to the current state of its parent,
* which could have been changed by cpuset just after it inherits the
* state from the parent and before it sits on the cgroup's task list.
*/
void cpuset_fork(struct task_struct *task)
{
if (task_css_is_root(task, cpuset_cgrp_id))
return;
set_cpus_allowed_ptr(task, &current->cpus_allowed);
task->mems_allowed = current->mems_allowed;
}
struct cgroup_subsys cpuset_cgrp_subsys = {
.css_alloc = cpuset_css_alloc,
.css_online = cpuset_css_online,
@ -2079,6 +2093,7 @@ struct cgroup_subsys cpuset_cgrp_subsys = {
.attach = cpuset_attach,
.post_attach = cpuset_post_attach,
.bind = cpuset_bind,
.fork = cpuset_fork,
.legacy_cftypes = files,
.early_init = true,
};