yama_ptracer_del can be called in softirq context, so
ptracer_relations_lock may be held in softirq context.
This patch replaces spin_[un]lock with spin_[un]lock_bh for
&ptracer_relations_lock to fix reported lockdep warning and
avoid possible dealock.
BugLink: http://bugs.launchpad.net/bugs/791019
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
struct ptrace_relation *entry, *relation = NULL;
added = kmalloc(sizeof(*added), GFP_KERNEL);
struct ptrace_relation *entry, *relation = NULL;
added = kmalloc(sizeof(*added), GFP_KERNEL);
- spin_lock(&ptracer_relations_lock);
+ spin_lock_bh(&ptracer_relations_lock);
list_for_each_entry(entry, &ptracer_relations, node)
if (entry->tracee == tracee) {
relation = entry;
list_for_each_entry(entry, &ptracer_relations, node)
if (entry->tracee == tracee) {
relation = entry;
relation->tracer = tracer;
unlock_out:
relation->tracer = tracer;
unlock_out:
- spin_unlock(&ptracer_relations_lock);
+ spin_unlock_bh(&ptracer_relations_lock);
if (added && added != relation)
kfree(added);
if (added && added != relation)
kfree(added);
struct ptrace_relation *relation;
struct list_head *list, *safe;
struct ptrace_relation *relation;
struct list_head *list, *safe;
- spin_lock(&ptracer_relations_lock);
+ spin_lock_bh(&ptracer_relations_lock);
list_for_each_safe(list, safe, &ptracer_relations) {
relation = list_entry(list, struct ptrace_relation, node);
if (relation->tracee == tracee ||
list_for_each_safe(list, safe, &ptracer_relations) {
relation = list_entry(list, struct ptrace_relation, node);
if (relation->tracee == tracee ||
- spin_unlock(&ptracer_relations_lock);
+ spin_unlock_bh(&ptracer_relations_lock);
struct ptrace_relation *relation;
struct task_struct *parent = NULL;
struct ptrace_relation *relation;
struct task_struct *parent = NULL;
- spin_lock(&ptracer_relations_lock);
+ spin_lock_bh(&ptracer_relations_lock);
rcu_read_lock();
read_lock(&tasklist_lock);
rcu_read_lock();
read_lock(&tasklist_lock);
if (task_is_descendant(parent, tracer))
rc = 1;
if (task_is_descendant(parent, tracer))
rc = 1;
- spin_unlock(&ptracer_relations_lock);
+ spin_unlock_bh(&ptracer_relations_lock);