pid: rely on common reference count behavior

brauner · brauner · commit 282879afa019 · 2025-11-11T10:01:32.000+01:00
Now that we changed the generic reference counting mechanism for all namespaces to never manipulate reference counts of initial namespaces we can drop the special handling for pid namespaces. Link: https://patch.msgid.link/20251110-work-namespace-nstree-fixes-v1-15-e8a9264e0fb9@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h
@@ -61,8 +61,7 @@ static inline struct pid_namespace *to_pid_ns(struct ns_common *ns)
 
 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
 {
-	if (ns != &init_pid_ns)
-		ns_ref_inc(ns);
+	ns_ref_inc(ns);
 	return ns;
 }
 
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
@@ -184,7 +184,7 @@ struct pid_namespace *copy_pid_ns(u64 flags,
 
 void put_pid_ns(struct pid_namespace *ns)
 {
-	if (ns && ns != &init_pid_ns && ns_ref_put(ns))
+	if (ns && ns_ref_put(ns))
 		schedule_work(&ns->work);
 }
 EXPORT_SYMBOL_GPL(put_pid_ns);

Original file line number	Diff line number	Diff line change
`@@ -61,8 +61,7 @@ static inline struct pid_namespace to_pid_ns(struct ns_common ns)`
`61`	`61`
`62`	`62`	`static inline struct pid_namespace get_pid_ns(struct pid_namespace ns)`
`63`	`63`	`{`
`64`		`- if (ns != &init_pid_ns)`
`65`		`- ns_ref_inc(ns);`
	`64`	`+ ns_ref_inc(ns);`
`66`	`65`	`return ns;`
`67`	`66`	`}`
`68`	`67`
Original file line number	Diff line number	Diff line change
`@@ -184,7 +184,7 @@ struct pid_namespace *copy_pid_ns(u64 flags,`
`184`	`184`
`185`	`185`	`void put_pid_ns(struct pid_namespace *ns)`
`186`	`186`	`{`
`187`		`- if (ns && ns != &init_pid_ns && ns_ref_put(ns))`
	`187`	`+ if (ns && ns_ref_put(ns))`
`188`	`188`	`schedule_work(&ns->work);`
`189`	`189`	`}`
`190`	`190`	`EXPORT_SYMBOL_GPL(put_pid_ns);`