[PATCH 14/17] ns: add asserts for initial namespace active reference counts
From: Christian Brauner <brauner@kernel.org>
Date: 2025-11-10 15:09:54
Also in:
bpf, cgroups, linux-fsdevel, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
They always remain fixed at one. Notice when that assumptions is broken. Signed-off-by: Christian Brauner <brauner@kernel.org> --- include/linux/ns_common.h | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/include/linux/ns_common.h b/include/linux/ns_common.h
index dfb6b798ba82..43f709ab846a 100644
--- a/include/linux/ns_common.h
+++ b/include/linux/ns_common.h@@ -69,6 +69,7 @@ static __always_inline __must_check bool __ns_ref_put(struct ns_common *ns) { if (is_ns_init_id(ns)) { VFS_WARN_ON_ONCE(__ns_ref_read(ns) != 1); + VFS_WARN_ON_ONCE(__ns_ref_active_read(ns) != 1); return false; } if (refcount_dec_and_test(&ns->__ns_ref)) {
@@ -82,6 +83,7 @@ static __always_inline __must_check bool __ns_ref_get(struct ns_common *ns) { if (is_ns_init_id(ns)) { VFS_WARN_ON_ONCE(__ns_ref_read(ns) != 1); + VFS_WARN_ON_ONCE(__ns_ref_active_read(ns) != 1); return true; } if (refcount_inc_not_zero(&ns->__ns_ref))
@@ -94,6 +96,7 @@ static __always_inline void __ns_ref_inc(struct ns_common *ns) { if (is_ns_init_id(ns)) { VFS_WARN_ON_ONCE(__ns_ref_read(ns) != 1); + VFS_WARN_ON_ONCE(__ns_ref_active_read(ns) != 1); return; } refcount_inc(&ns->__ns_ref);
@@ -104,6 +107,7 @@ static __always_inline __must_check bool __ns_ref_dec_and_lock(struct ns_common { if (is_ns_init_id(ns)) { VFS_WARN_ON_ONCE(__ns_ref_read(ns) != 1); + VFS_WARN_ON_ONCE(__ns_ref_active_read(ns) != 1); return false; } return refcount_dec_and_lock(&ns->__ns_ref, ns_lock);
--
2.47.3