From: Thomas Gleixner <tglx@linutronix.de>
Date: Fri, 22 Jul 2011 08:07:08 +0200
Subject: signal: Make __lock_task_sighand() RT aware
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git
Git-commit: efa795726587e73e29431e6a72efccc66f0800d6
Patch-mainline: Queued in subsystem maintainer repository
References: SLE Realtime Extension

local_irq_save() + spin_lock(&sighand->siglock) does not work on
-RT. Use the nort variants.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Mike Galbraith <mgalbraith@suse.de>
---
 kernel/signal.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1295,12 +1295,12 @@ struct sighand_struct *__lock_task_sigha
 		 * Disable interrupts early to avoid deadlocks.
 		 * See rcu_read_unlock() comment header for details.
 		 */
-		local_irq_save(*flags);
+		local_irq_save_nort(*flags);
 		rcu_read_lock();
 		sighand = rcu_dereference(tsk->sighand);
 		if (unlikely(sighand == NULL)) {
 			rcu_read_unlock();
-			local_irq_restore(*flags);
+			local_irq_restore_nort(*flags);
 			break;
 		}
 		/*
@@ -1321,7 +1321,7 @@ struct sighand_struct *__lock_task_sigha
 		}
 		spin_unlock(&sighand->siglock);
 		rcu_read_unlock();
-		local_irq_restore(*flags);
+		local_irq_restore_nort(*flags);
 	}
 
 	return sighand;