The patch below does not apply to the 3.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 4449a51a7c281602d3a385044ab928322a122a02 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov <[email protected]> Date: Fri, 8 Aug 2014 14:19:17 -0700 Subject: [PATCH] vm_is_stack: use for_each_thread() rather then buggy while_each_thread() 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]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> diff --git a/mm/util.c b/mm/util.c index 7b6608df2ee8..093c973f1697 100644 --- a/mm/util.c +++ b/mm/util.c @@ -183,17 +183,14 @@ pid_t vm_is_stack(struct task_struct *task, 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(); } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
