procfs: disable per-task stack usage on NOMMU

It needs walk_page_range().

Reported-by: Michal Simek <monstr@monstr.eu>
Tested-by: Michal Simek <monstr@monstr.eu>
Cc: Stefani Seibold <stefani@seibold.net>
Cc: David Howells <dhowells@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 0c6bc602e6c4..07f77a7945c3 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -322,6 +322,8 @@ static inline void task_context_switch_counts(struct seq_file *m,
                         p->nivcsw);
 }
 
+#ifdef CONFIG_MMU
+
 struct stack_stats {
         struct vm_area_struct *vma;
         unsigned long   startpage;
@@ -402,6 +404,11 @@ static inline void task_show_stack_usage(struct seq_file *m,
                 mmput(mm);
         }
 }
+#else
+static void task_show_stack_usage(struct seq_file *m, struct task_struct *task)
+{
+}
+#endif          /* CONFIG_MMU */
 
 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
                         struct pid *pid, struct task_struct *task)