5 files changed, 12 insertions, 38 deletions

diff --git a/fs/proc/array.c b/fs/proc/array.c
index df2b703b9d0f..7c99c1cf7e5c 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -353,9 +353,6 @@ int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
         task_cap(m, task);
         task_cpus_allowed(m, task);
         cpuset_task_status_allowed(m, task);
-#if defined(CONFIG_S390)
-        task_show_regs(m, task);
-#endif
         task_context_switch_counts(m, task);
         return 0;
 }
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 9d096e82b201..d49c4b5d2c3e 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 176ce4cda68a..d6a7ca1fdac5 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 d9396a4fc7ff..927cbd115e53 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 09a1f92a34ef..8eb2522111c5 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 = {