powerpc: Initialise paca.data_offset with poison
authorMichael Ellerman <michael@ellerman.id.au>
Fri, 7 Sep 2012 15:31:44 +0000 (15:31 +0000)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Sun, 9 Sep 2012 23:35:27 +0000 (09:35 +1000)
It's possible for the cpu_possible_mask to change between the time we
initialise the pacas and the time we setup per_cpu areas.

Obviously impossible cpus shouldn't ever be running, but stranger things
have happened. So be paranoid and initialise data_offset with a poison
value in case we don't set it up later.

Based on a patch from Anton Blanchard.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/kernel/paca.c

index fbe1a12..cd6da85 100644 (file)
@@ -142,6 +142,7 @@ void __init initialise_paca(struct paca_struct *new_paca, int cpu)
        new_paca->hw_cpu_id = 0xffff;
        new_paca->kexec_state = KEXEC_STATE_NONE;
        new_paca->__current = &init_task;
+       new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL;
 #ifdef CONFIG_PPC_STD_MMU_64
        new_paca->slb_shadow_ptr = &slb_shadow[cpu];
 #endif /* CONFIG_PPC_STD_MMU_64 */