s390: remove arch_early_irq_init()

Allocate early async stack like other early stacks and get rid of
arch_early_irq_init(). This way the async stack is allocated earlier,
and handled like all other stacks.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

arch/s390/kernel/setup.c

@@ -386,17 +386,6 @@ void __init arch_call_rest_init(void)
 	rest_init();
 }
 
-int __init arch_early_irq_init(void)
-{
-	unsigned long stack;
-
-	stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
-	if (!stack)
-		panic("Couldn't allocate async stack");
-	S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
-	return 0;
-}
-
 static unsigned long __init stack_alloc_early(void)
 {
 	unsigned long stack;
@@ -453,6 +442,7 @@ static void __init setup_lowcore(void)
 	 */
 	restart_stack = (void *)(stack_alloc_early() + STACK_INIT_OFFSET);
 	lc->mcck_stack = stack_alloc_early() + STACK_INIT_OFFSET;
+	lc->async_stack = stack_alloc_early() + STACK_INIT_OFFSET;
 	lc->nodat_stack = stack_alloc_early() + STACK_INIT_OFFSET;
 	lc->kernel_stack = S390_lowcore.kernel_stack;
 	/*

arch/s390/kernel/smp.c

@@ -1293,8 +1293,8 @@ int __init smp_reinit_ipl_cpu(void)
 	local_mcck_enable();
 	local_irq_restore(flags);
 
-	free_pages(lc_ipl->async_stack - STACK_INIT_OFFSET, THREAD_SIZE_ORDER);
 	memblock_free_late(__pa(lc_ipl->mcck_stack - STACK_INIT_OFFSET), THREAD_SIZE);
+	memblock_free_late(__pa(lc_ipl->async_stack - STACK_INIT_OFFSET), THREAD_SIZE);
 	memblock_free_late(__pa(lc_ipl->nodat_stack - STACK_INIT_OFFSET), THREAD_SIZE);
 	memblock_free_late(__pa(lc_ipl), sizeof(*lc_ipl));
 	return 0;