This is a note to let you know that I've just added the patch titled

    vm_is_stack: use for_each_thread() rather then buggy while_each_thread()

to the 3.10-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     vm_is_stack-use-for_each_thread-rather-then-buggy-while_each_thread.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 4449a51a7c281602d3a385044ab928322a122a02 Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <[email protected]>
Date: Fri, 8 Aug 2014 14:19:17 -0700
Subject: vm_is_stack: use for_each_thread() rather then buggy 
while_each_thread()

From: Oleg Nesterov <[email protected]>

commit 4449a51a7c281602d3a385044ab928322a122a02 upstream.

Aleksei hit the soft lockup during reading /proc/PID/smaps.  David
investigated the problem and suggested the right fix.

while_each_thread() is racy and should die, this patch updates
vm_is_stack().

Signed-off-by: Oleg Nesterov <[email protected]>
Reported-by: Aleksei Besogonov <[email protected]>
Tested-by: Aleksei Besogonov <[email protected]>
Suggested-by: David Rientjes <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 mm/util.c |    9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

--- a/mm/util.c
+++ b/mm/util.c
@@ -272,17 +272,14 @@ pid_t vm_is_stack(struct task_struct *ta
 
        if (in_group) {
                struct task_struct *t;
-               rcu_read_lock();
-               if (!pid_alive(task))
-                       goto done;
 
-               t = task;
-               do {
+               rcu_read_lock();
+               for_each_thread(task, t) {
                        if (vm_is_stack_for_task(t, vma)) {
                                ret = t->pid;
                                goto done;
                        }
-               } while_each_thread(task, t);
+               }
 done:
                rcu_read_unlock();
        }


Patches currently in stable-queue which might be from [email protected] are

queue-3.10/vm_is_stack-use-for_each_thread-rather-then-buggy-while_each_thread.patch
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