On Mon, Jan 19, 2009 at 10:43 PM, Li Zefan <lizf@xxxxxxxxxxxxxx> wrote: > I fixed a bug in cgroup_clone() in Linus' tree (commit 7b574b7), without > noticing there was a cleanup patch in -mm tree that should be rebased > (now commit 104cbd5), thus resulted in lock inconsistency. > > Signed-off-by: Li Zefan <lizf@xxxxxxxxxxxxxx> Acked-by: Paul Menage <menage@xxxxxxxxxx> Thanks. > --- > > for 2.6.29 > > --- > kernel/cgroup.c | 13 +++++++------ > 1 files changed, 7 insertions(+), 6 deletions(-) > > diff --git a/kernel/cgroup.c b/kernel/cgroup.c > index c298310..a5826f3 100644 > --- a/kernel/cgroup.c > +++ b/kernel/cgroup.c > @@ -2991,20 +2991,21 @@ int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *subsys, > mutex_unlock(&cgroup_mutex); > return 0; > } > - task_lock(tsk); > - cg = tsk->cgroups; > - parent = task_cgroup(tsk, subsys->subsys_id); > > /* Pin the hierarchy */ > - if (!atomic_inc_not_zero(&parent->root->sb->s_active)) { > + if (!atomic_inc_not_zero(&root->sb->s_active)) { > /* We race with the final deactivate_super() */ > mutex_unlock(&cgroup_mutex); > return 0; > } > > /* Keep the cgroup alive */ > + task_lock(tsk); > + parent = task_cgroup(tsk, subsys->subsys_id); > + cg = tsk->cgroups; > get_css_set(cg); > task_unlock(tsk); > + > mutex_unlock(&cgroup_mutex); > > /* Now do the VFS work to create a cgroup */ > @@ -3043,7 +3044,7 @@ int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *subsys, > mutex_unlock(&inode->i_mutex); > put_css_set(cg); > > - deactivate_super(parent->root->sb); > + deactivate_super(root->sb); > /* The cgroup is still accessible in the VFS, but > * we're not going to try to rmdir() it at this > * point. */ > @@ -3069,7 +3070,7 @@ int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *subsys, > mutex_lock(&cgroup_mutex); > put_css_set(cg); > mutex_unlock(&cgroup_mutex); > - deactivate_super(parent->root->sb); > + deactivate_super(root->sb); > return ret; > } > > -- > 1.5.4.rc3 > > > _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers