KVM: PPC: Use preregistered memory API to access TCE list

[mirror_ubuntu-zesty-kernel.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 2ee9ec3051b20774b118a57e4609f30e87bf82be..36672b678cce657d43b3a40c4feafc7f4845a516 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;
        }
@@ -5221,6 +5222,11 @@ 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;
@@ -5288,11 +5294,6 @@ 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:
@@ -5300,9 +5301,6 @@ 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,
@@ -6501,15 +6499,16 @@ static __init int cgroup_namespaces_init(void)
 subsys_initcall(cgroup_namespaces_init);
 
 #ifdef CONFIG_CGROUP_BPF
-void cgroup_bpf_update(struct cgroup *cgrp,
-                      struct bpf_prog *prog,
-                      enum bpf_attach_type type)
+int cgroup_bpf_update(struct cgroup *cgrp, struct bpf_prog *prog,
+                     enum bpf_attach_type type, bool overridable)
 {
        struct cgroup *parent = cgroup_parent(cgrp);
+       int ret;
 
        mutex_lock(&cgroup_mutex);
-       __cgroup_bpf_update(cgrp, parent, prog, type);
+       ret = __cgroup_bpf_update(cgrp, parent, prog, type, overridable);
        mutex_unlock(&cgroup_mutex);
+       return ret;
 }
 #endif /* CONFIG_CGROUP_BPF */