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From: Ruoyu Wang <ruoyuw560@gmail.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tejun Heo <tj@kernel.org>,
	driver-core@lists.linux.dev, linux-kernel@vger.kernel.org,
	Ruoyu Wang <ruoyuw560@gmail.com>
Subject: [PATCH] kernfs: use nofail allocation for global locks
Date: Mon,  8 Jun 2026 14:36:55 +0800	[thread overview]
Message-ID: <20260608063655.69-1-ruoyuw560@gmail.com> (raw)

kernfs_lock_init() allocates the global kernfs lock storage during init
and then calls kernfs_mutex_init(), which initializes mutexes through the
allocated pointer. A WARN_ON() does not stop execution, so allocation
failure would still dereference NULL.

The lock storage is required for kernfs to operate. Use a nofail
GFP_KERNEL allocation so the init path does not continue without the
required object.

Signed-off-by: Ruoyu Wang <ruoyuw560@gmail.com>
---
 fs/kernfs/mount.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c
index 6e3217b6e4811..6cf8e71e5bd08 100644
--- a/fs/kernfs/mount.c
+++ b/fs/kernfs/mount.c
@@ -451,8 +451,8 @@ static void __init kernfs_mutex_init(void)
 
 static void __init kernfs_lock_init(void)
 {
-	kernfs_locks = kmalloc_obj(struct kernfs_global_locks);
-	WARN_ON(!kernfs_locks);
+	kernfs_locks = kmalloc_obj(struct kernfs_global_locks,
+				   GFP_KERNEL | __GFP_NOFAIL);
 
 	kernfs_mutex_init();
 }
-- 
2.51.0


             reply	other threads:[~2026-06-08  6:37 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-08  6:36 Ruoyu Wang [this message]
2026-06-08 12:25 ` [PATCH] kernfs: use nofail allocation for global locks Greg Kroah-Hartman

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