4 files changed, 12 insertions, 35 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 9d096e82b20..d49c4b5d2c3 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2620,35 +2620,6 @@ static const struct pid_entry proc_base_stuff[] = {
 		&proc_self_inode_operations, NULL, {}),
 };
 
-/*
- *	Exceptional case: normally we are not allowed to unhash a busy
- * directory. In this case, however, we can do it - no aliasing problems
- * due to the way we treat inodes.
- */
-static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
-{
-	struct inode *inode;
-	struct task_struct *task;
-
-	if (nd->flags & LOOKUP_RCU)
-		return -ECHILD;
-
-	inode = dentry->d_inode;
-	task = get_proc_task(inode);
-	if (task) {
-		put_task_struct(task);
-		return 1;
-	}
-	d_drop(dentry);
-	return 0;
-}
-
-static const struct dentry_operations proc_base_dentry_operations =
-{
-	.d_revalidate	= proc_base_revalidate,
-	.d_delete	= pid_delete_dentry,
-};
-
 static struct dentry *proc_base_instantiate(struct inode *dir,
 	struct dentry *dentry, struct task_struct *task, const void *ptr)
 {
@@ -2685,7 +2656,6 @@ static struct dentry *proc_base_instantiate(struct inode *dir,
 	if (p->fop)
 		inode->i_fop = p->fop;
 	ei->op = p->op;
-	d_set_d_op(dentry, &proc_base_dentry_operations);
 	d_add(dentry, inode);
 	error = NULL;
 out:
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 176ce4cda68..d6a7ca1fdac 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -27,6 +27,7 @@
 static void proc_evict_inode(struct inode *inode)
 {
 	struct proc_dir_entry *de;
+	struct ctl_table_header *head;
 
 	truncate_inode_pages(&inode->i_data, 0);
 	end_writeback(inode);
@@ -38,8 +39,11 @@ static void proc_evict_inode(struct inode *inode)
 	de = PROC_I(inode)->pde;
 	if (de)
 		pde_put(de);
-	if (PROC_I(inode)->sysctl)
-		sysctl_head_put(PROC_I(inode)->sysctl);
+	head = PROC_I(inode)->sysctl;
+	if (head) {
+		rcu_assign_pointer(PROC_I(inode)->sysctl, NULL);
+		sysctl_head_put(head);
+	}
 }
 
 struct vfsmount *proc_mnt;
diff --git a/fs/proc/proc_devtree.c b/fs/proc/proc_devtree.c
index d9396a4fc7f..927cbd115e5 100644
--- a/fs/proc/proc_devtree.c
+++ b/fs/proc/proc_devtree.c
@@ -233,7 +233,7 @@ void __init proc_device_tree_init(void)
 		return;
 	root = of_find_node_by_path("/");
 	if (root == NULL) {
-		printk(KERN_ERR "/proc/device-tree: can't find root\n");
+		pr_debug("/proc/device-tree: can't find root\n");
 		return;
 	}
 	proc_device_tree_add_node(root, proc_device_tree);
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 09a1f92a34e..8eb2522111c 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -408,15 +408,18 @@ static int proc_sys_compare(const struct dentry *parent,
 		const struct dentry *dentry, const struct inode *inode,
 		unsigned int len, const char *str, const struct qstr *name)
 {
+	struct ctl_table_header *head;
 	/* Although proc doesn't have negative dentries, rcu-walk means
 	 * that inode here can be NULL */
+	/* AV: can it, indeed? */
 	if (!inode)
-		return 0;
+		return 1;
 	if (name->len != len)
 		return 1;
 	if (memcmp(name->name, str, len))
 		return 1;
-	return !sysctl_is_seen(PROC_I(inode)->sysctl);
+	head = rcu_dereference(PROC_I(inode)->sysctl);
+	return !head || !sysctl_is_seen(head);
 }
 
 static const struct dentry_operations proc_sys_dentry_operations = {