2 files changed, 15 insertions, 8 deletions

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index be35ffae10f0..1457aa0a08f1 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -386,6 +386,8 @@ static void __init smp_create_idle(unsigned int cpu)
                 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 497ec059bc82..cf8705e32d60 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -44,13 +44,13 @@ static void slb_allocate(unsigned long ea)
         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 @@ void slb_initialize(void)
 
         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");
 }