MIPS: VDSO: Prevent use of smp_processor_id()

[android-x86/kernel.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 85bc9be..bb0cf1c 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2920,11 +2920,12 @@ static ssize_t __cgroup_procs_write(struct kernfs_open_file *of, char *buf,
                tsk = tsk->group_leader;
 
        /*
-        * Workqueue threads may acquire PF_NO_SETAFFINITY and become
-        * trapped in a cpuset, or RT worker may be born in a cgroup
-        * with no rt_runtime allocated.  Just say no.
+        * kthreads may acquire PF_NO_SETAFFINITY during initialization.
+        * If userland migrates such a kthread to a non-root cgroup, it can
+        * become trapped in a cpuset, or RT kthread may be born in a
+        * cgroup with no rt_runtime allocated.  Just say no.
         */
-       if (tsk == kthreadd_task || (tsk->flags & PF_NO_SETAFFINITY)) {
+       if (tsk->no_cgroup_migration || (tsk->flags & PF_NO_SETAFFINITY)) {
                ret = -EINVAL;
                goto out_unlock_rcu;
        }
@@ -3486,11 +3487,11 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
        cgrp->subtree_control &= ~disable;
 
        ret = cgroup_apply_control(cgrp);
-
        cgroup_finalize_control(cgrp, ret);
+       if (ret)
+               goto out_unlock;
 
        kernfs_activate(cgrp->kn);
-       ret = 0;
 out_unlock:
        cgroup_kn_unlock(of->kn);
        return ret ?: nbytes;
@@ -4385,7 +4386,11 @@ int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from)
         */
        do {
                css_task_iter_start(&from->self, &it);
-               task = css_task_iter_next(&it);
+
+               do {
+                       task = css_task_iter_next(&it);
+               } while (task && (task->flags & PF_EXITING));
+
                if (task)
                        get_task_struct(task);
                css_task_iter_end(&it);
@@ -5219,6 +5224,11 @@ err_free_css:
        return ERR_PTR(err);
 }
 
+/*
+ * The returned cgroup is fully initialized including its control mask, but
+ * it isn't associated with its kernfs_node and doesn't have the control
+ * mask applied.
+ */
 static struct cgroup *cgroup_create(struct cgroup *parent)
 {
        struct cgroup_root *root = parent->root;
@@ -5283,11 +5293,6 @@ static struct cgroup *cgroup_create(struct cgroup *parent)
 
        cgroup_propagate_control(cgrp);
 
-       /* @cgrp doesn't have dir yet so the following will only create csses */
-       ret = cgroup_apply_control_enable(cgrp);
-       if (ret)
-               goto out_destroy;
-
        return cgrp;
 
 out_cancel_ref:
@@ -5295,9 +5300,6 @@ out_cancel_ref:
 out_free_cgrp:
        kfree(cgrp);
        return ERR_PTR(ret);
-out_destroy:
-       cgroup_destroy_locked(cgrp);
-       return ERR_PTR(ret);
 }
 
 static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
@@ -5409,6 +5411,11 @@ static void kill_css(struct cgroup_subsys_state *css)
 {
        lockdep_assert_held(&cgroup_mutex);
 
+       if (css->flags & CSS_DYING)
+               return;
+
+       css->flags |= CSS_DYING;
+
        /*
         * This must happen before css is disassociated with its cgroup.
         * See seq_css() for details.
@@ -5715,6 +5722,10 @@ int __init cgroup_init(void)
 
                if (ss->bind)
                        ss->bind(init_css_set.subsys[ssid]);
+
+               mutex_lock(&cgroup_mutex);
+               css_populate_dir(init_css_set.subsys[ssid]);
+               mutex_unlock(&cgroup_mutex);
        }
 
        /* init_css_set.subsys[] has been updated, re-hash */