diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 4f80cf1ce77b..3e57a00b8cba 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -1213,7 +1213,7 @@ do_user_signal:			/* r10 contains MSR_KERNEL here */
 	stw	r3,_TRAP(r1)
 2:	addi	r3,r1,STACK_FRAME_OVERHEAD
 	mr	r4,r9
-	bl	do_signal
+	bl	do_notify_resume
 	REST_NVGPRS(r1)
 	b	recheck
 
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index d834425186ae..866462cbe2d8 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -751,12 +751,16 @@ user_work:
 
 	andi.	r0,r4,_TIF_NEED_RESCHED
 	beq	1f
+	li	r5,1
+	TRACE_AND_RESTORE_IRQ(r5);
 	bl	.schedule
 	b	.ret_from_except_lite
 
 1:	bl	.save_nvgprs
+	li	r5,1
+	TRACE_AND_RESTORE_IRQ(r5);
 	addi	r3,r1,STACK_FRAME_OVERHEAD
-	bl	.do_signal
+	bl	.do_notify_resume
 	b	.ret_from_except
 
 unrecov_restore:
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 3844ca7c5099..15c5a4f6de01 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -774,8 +774,8 @@ alignment_common:
 program_check_common:
 	EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
 	bl	.save_nvgprs
-	addi	r3,r1,STACK_FRAME_OVERHEAD
 	DISABLE_INTS
+	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.program_check_exception
 	b	.ret_from_except
 
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 2300426e531a..ac6e437b1021 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -11,6 +11,7 @@
 
 #include <linux/tracehook.h>
 #include <linux/signal.h>
+#include <linux/key.h>
 #include <asm/hw_breakpoint.h>
 #include <asm/uaccess.h>
 #include <asm/unistd.h>
@@ -113,8 +114,9 @@ static void check_syscall_restart(struct pt_regs *regs, struct k_sigaction *ka,
 	}
 }
 
-static int do_signal_pending(sigset_t *oldset, struct pt_regs *regs)
+static int do_signal(struct pt_regs *regs)
 {
+	sigset_t *oldset;
 	siginfo_t info;
 	int signr;
 	struct k_sigaction ka;
@@ -123,7 +125,7 @@ static int do_signal_pending(sigset_t *oldset, struct pt_regs *regs)
 
 	if (current_thread_info()->local_flags & _TLF_RESTORE_SIGMASK)
 		oldset = &current->saved_sigmask;
-	else if (!oldset)
+	else
 		oldset = &current->blocked;
 
 	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
@@ -191,14 +193,16 @@ static int do_signal_pending(sigset_t *oldset, struct pt_regs *regs)
 	return ret;
 }
 
-void do_signal(struct pt_regs *regs, unsigned long thread_info_flags)
+void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags)
 {
 	if (thread_info_flags & _TIF_SIGPENDING)
-		do_signal_pending(NULL, regs);
+		do_signal(regs);
 
 	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
 		clear_thread_flag(TIF_NOTIFY_RESUME);
 		tracehook_notify_resume(regs);
+		if (current->replacement_session_keyring)
+			key_replace_session_keyring();
 	}
 }
 
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index 6c0ddfc0603e..8dde973aaaf5 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -12,7 +12,7 @@
 
 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
 
-extern void do_signal(struct pt_regs *regs, unsigned long thread_info_flags);
+extern void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags);
 
 extern void __user * get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
 				  size_t frame_size, int is_32);
diff --git a/arch/powerpc/platforms/wsp/smp.c b/arch/powerpc/platforms/wsp/smp.c
index 71bd105f3863..0ba103ae83a5 100644
--- a/arch/powerpc/platforms/wsp/smp.c
+++ b/arch/powerpc/platforms/wsp/smp.c
@@ -71,7 +71,7 @@ int __devinit smp_a2_kick_cpu(int nr)
 
 static int __init smp_a2_probe(void)
 {
-	return cpus_weight(cpu_possible_map);
+	return num_possible_cpus();
 }
 
 static struct smp_ops_t a2_smp_ops = {
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
index 7dbc4a83c45c..78a666d1e5f5 100644
--- a/drivers/cpuidle/Kconfig
+++ b/drivers/cpuidle/Kconfig
@@ -1,7 +1,7 @@
 
 config CPU_IDLE
 	bool "CPU idle PM support"
-	default ACPI
+	default y if ACPI || PPC_PSERIES
 	help
 	  CPU idle is a generic framework for supporting software-controlled
 	  idle processor power management.  It includes modular cross-platform