diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index be35ffae..1457aa0 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -386,6 +386,8 @@
 		panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
 #ifdef CONFIG_PPC64
 	paca[cpu].__current = p;
+	paca[cpu].kstack = (unsigned long) task_thread_info(p)
+		+ THREAD_SIZE - STACK_FRAME_OVERHEAD;
 #endif
 	current_set[cpu] = task_thread_info(p);
 	task_thread_info(p)->cpu = cpu;
diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index 497ec05..cf8705e 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -44,13 +44,13 @@
 	slb_allocate_realmode(ea);
 }
 
+#define slb_esid_mask(ssize)	\
+	(((ssize) == MMU_SEGSIZE_256M)? ESID_MASK: ESID_MASK_1T)
+
 static inline unsigned long mk_esid_data(unsigned long ea, int ssize,
 					 unsigned long slot)
 {
-	unsigned long mask;
-
-	mask = (ssize == MMU_SEGSIZE_256M)? ESID_MASK: ESID_MASK_1T;
-	return (ea & mask) | SLB_ESID_V | slot;
+	return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot;
 }
 
 #define slb_vsid_shift(ssize)	\
@@ -301,11 +301,16 @@
 
 	create_shadowed_slbe(VMALLOC_START, mmu_kernel_ssize, vflags, 1);
 
+	/* For the boot cpu, we're running on the stack in init_thread_union,
+	 * which is in the first segment of the linear mapping, and also
+	 * get_paca()->kstack hasn't been initialized yet.
+	 * For secondary cpus, we need to bolt the kernel stack entry now.
+	 */
 	slb_shadow_clear(2);
+	if (raw_smp_processor_id() != boot_cpuid &&
+	    (get_paca()->kstack & slb_esid_mask(mmu_kernel_ssize)) > PAGE_OFFSET)
+		create_shadowed_slbe(get_paca()->kstack,
+				     mmu_kernel_ssize, lflags, 2);
 
-	/* We don't bolt the stack for the time being - we're in boot,
-	 * so the stack is in the bolted segment.  By the time it goes
-	 * elsewhere, we'll call _switch() which will bolt in the new
-	 * one. */
 	asm volatile("isync":::"memory");
 }