fs/proc: Don't lock root inode when creating "self" and "thread-self"

proc_setup_self() and proc_setup_thread_self() are only called from
proc_fill_super() which is before the filesystem is "live".  So there is
no need to lock the root directory when adding "self" and "thread-self".
This is clear from simple_fill_super() which provides similar
functionality for other filesystems and does not lock anything.

The locking is not harmful, except that it may be confusing to a reader.
As part of an effort to centralise all locking for directories for
name-based operations (prior to changing some locking rules), it is
simplest to remove the locking here.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20260224222542.3458677-3-neilb@ownmail.net
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/proc/self.c b/fs/proc/self.c
index 62d2c0cfe35c58b9ab3d6a603984aff2c0bdbb4e..56adf1c68f7accdf49a3c70be7ed761c091aafb5 100644 (file)
--- a/fs/proc/self.c
+++ b/fs/proc/self.c
@@ -35,11 +35,9 @@ unsigned self_inum __ro_after_init;
 
 int proc_setup_self(struct super_block *s)
 {
-       struct inode *root_inode = d_inode(s->s_root);
        struct dentry *self;
        int ret = -ENOMEM;
 
-       inode_lock(root_inode);
        self = d_alloc_name(s->s_root, "self");
        if (self) {
                struct inode *inode = new_inode(s);
@@ -55,7 +53,6 @@ int proc_setup_self(struct super_block *s)
                }
                dput(self);
        }
-       inode_unlock(root_inode);
 
        if (ret)
                pr_err("proc_fill_super: can't allocate /proc/self\n");

diff --git a/fs/proc/thread_self.c b/fs/proc/thread_self.c
index d6113dbe58e059e10c7dd93eecc40e06f3afec39..61ac62c3fd9f8f82eaa196ebf5febdb707172d05 100644 (file)
--- a/fs/proc/thread_self.c
+++ b/fs/proc/thread_self.c
@@ -35,11 +35,9 @@ unsigned thread_self_inum __ro_after_init;
 
 int proc_setup_thread_self(struct super_block *s)
 {
-       struct inode *root_inode = d_inode(s->s_root);
        struct dentry *thread_self;
        int ret = -ENOMEM;
 
-       inode_lock(root_inode);
        thread_self = d_alloc_name(s->s_root, "thread-self");
        if (thread_self) {
                struct inode *inode = new_inode(s);
@@ -55,7 +53,6 @@ int proc_setup_thread_self(struct super_block *s)
                }
                dput(thread_self);
        }
-       inode_unlock(root_inode);
 
        if (ret)
                pr_err("proc_fill_super: can't allocate /proc/thread-self\n");