[PATCH] powerpc/nohash: Allocate stale_map[cpu] on CPU_UP_PREPARE not CPU_ONLINE

[Michael Ellerman]

Currently we allocate the stale_map for a cpu when it comes online,
this leaves open a small window where a process can be scheduled
on the cpu before the stale_map is allocated. Instead allocate
the stale_map at CPU_UP_PREPARE time, that way it will be always
available before tasks start running.

Signed-off-by: Michael Ellerman <michael at ellerman.id.au>
---
 arch/powerpc/mm/mmu_context_nohash.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c
index c0aab52..1bde0e8 100644
--- a/arch/powerpc/mm/mmu_context_nohash.c
+++ b/arch/powerpc/mm/mmu_context_nohash.c
@@ -338,8 +338,8 @@ static int __cpuinit mmu_context_cpu_notify(struct notifier_block *self,
 		return NOTIFY_OK;
 
 	switch (action) {
-	case CPU_ONLINE:
-	case CPU_ONLINE_FROZEN:
+	case CPU_UP_PREPARE:
+	case CPU_UP_PREPARE_FROZEN:
 		pr_devel("MMU: Allocating stale context map for CPU %d\n", cpu);
 		stale_map[cpu] = kzalloc(CTX_MAP_SIZE, GFP_KERNEL);
 		break;
-- 
1.7.1