1 files changed, 28 insertions, 8 deletions

diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index a73d2d700973..ff1811ac6c81 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -74,6 +74,22 @@ static inline void slb_shadow_clear(unsigned long entry)
         get_slb_shadow()->save_area[entry].esid = 0;
 }
 
+static inline void create_shadowed_slbe(unsigned long ea, unsigned long flags,
+                                        unsigned long entry)
+{
+        /*
+         * Updating the shadow buffer before writing the SLB ensures
+         * we don't get a stale entry here if we get preempted by PHYP
+         * between these two statements.
+         */
+        slb_shadow_update(ea, flags, entry);
+
+        asm volatile("slbmte  %0,%1" :
+                     : "r" (mk_vsid_data(ea, flags)),
+                       "r" (mk_esid_data(ea, entry))
+                     : "memory" );
+}
+
 void slb_flush_and_rebolt(void)
 {
         /* If you change this make sure you change SLB_NUM_BOLTED
@@ -226,12 +242,16 @@ void slb_initialize(void)
         vflags = SLB_VSID_KERNEL | vmalloc_llp;
 
         /* Invalidate the entire SLB (even slot 0) & all the ERATS */
-        slb_shadow_update(PAGE_OFFSET, lflags, 0);
-        asm volatile("isync; slbia; sync; slbmte  %0,%1; isync" ::
-                     "r" (get_slb_shadow()->save_area[0].vsid),
-                     "r" (get_slb_shadow()->save_area[0].esid) : "memory");
-
-        slb_shadow_update(VMALLOC_START, vflags, 1);
-
-        slb_flush_and_rebolt();
+        asm volatile("isync":::"memory");
+        asm volatile("slbmte  %0,%0"::"r" (0) : "memory");
+        asm volatile("isync; slbia; isync":::"memory");
+        create_shadowed_slbe(PAGE_OFFSET, lflags, 0);
+
+        create_shadowed_slbe(VMALLOC_START, vflags, 1);
+
+        /* 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");
 }