Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 398f8787 authored by Tejun Heo's avatar Tejun Heo
Browse files

Merge branch 'cgroup/for-3.14-fixes' into cgroup/for-3.15 



Pull for-3.14-fixes to receive 0ab02ca8 ("cgroup: protect
modifications to cgroup_idr with cgroup_mutex") prior to kernfs
conversion series to avoid non-trivial conflicts.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parents f7cef064 0ab02ca8

include/linux/cgroup.h

+2 −0
Original line number Diff line number Diff line
@@ -151,6 +151,8 @@ struct cgroup { 
	 *

	 * The ID of the root cgroup is always 0, and a new cgroup

	 * will be assigned with a smallest available ID.

	 *

	 * Allocating/Removing ID must be protected by cgroup_mutex.

	 */

	int id;

kernel/cgroup.c

+18 −16
Original line number Diff line number Diff line
@@ -850,7 +850,9 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode) 
		 * per-subsystem and moved to css->id so that lookups are

		 * successful until the target css is released.

		 */

		mutex_lock(&cgroup_mutex);

		idr_remove(&cgrp->root->cgroup_idr, cgrp->id);

		mutex_unlock(&cgroup_mutex);

		cgrp->id = -1;



		call_rcu(&cgrp->rcu_head, cgroup_free_rcu);
@@ -4091,16 +4093,6 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, 
	}

	rcu_assign_pointer(cgrp->name, name);



	/*

	 * Temporarily set the pointer to NULL, so idr_find() won't return

	 * a half-baked cgroup.

	 */

	cgrp->id = idr_alloc(&root->cgroup_idr, NULL, 1, 0, GFP_KERNEL);

	if (cgrp->id < 0) {

		err = -ENOMEM;

		goto err_free_name;

	}



	/*

	 * Only live parents can have children.  Note that the liveliness

	 * check isn't strictly necessary because cgroup_mkdir() and
@@ -4110,7 +4102,17 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, 
	 */

	if (!cgroup_lock_live_group(parent)) {

		err = -ENODEV;

		goto err_free_id;

		goto err_free_name;

	}



	/*

	 * Temporarily set the pointer to NULL, so idr_find() won't return

	 * a half-baked cgroup.

	 */

	cgrp->id = idr_alloc(&root->cgroup_idr, NULL, 1, 0, GFP_KERNEL);

	if (cgrp->id < 0) {

		err = -ENOMEM;

		goto err_unlock;

	}



	/* Grab a reference on the superblock so the hierarchy doesn't
@@ -4142,7 +4144,7 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, 
	 */

	err = cgroup_create_file(dentry, S_IFDIR | mode, sb);

	if (err < 0)

		goto err_unlock;

		goto err_free_id;

	lockdep_assert_held(&dentry->d_inode->i_mutex);



	cgrp->serial_nr = cgroup_serial_nr_next++;
@@ -4178,12 +4180,12 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, 


	return 0;



err_unlock:

	mutex_unlock(&cgroup_mutex);

	/* Release the reference count that we took on the superblock */

	deactivate_super(sb);

err_free_id:

	idr_remove(&root->cgroup_idr, cgrp->id);

	/* Release the reference count that we took on the superblock */

	deactivate_super(sb);

err_unlock:

	mutex_unlock(&cgroup_mutex);

err_free_name:

	kfree(rcu_dereference_raw(cgrp->name));

err_free_cgrp: