powerpc/mm: Use the required number of VSID bits in slbmte

ASM_VSID_SCRAMBLE can leave non-zero bits in the high 28 bits of the result
for 256MB segment (40 bits for 1T segment). Properly mask them before using
the values in slbmte

Reviewed-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 10 insertions, 2 deletions

diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S
index e132dc6ed1a9..3b75f19aaa22 100644
--- a/arch/powerpc/mm/slb_low.S
+++ b/arch/powerpc/mm/slb_low.S
@@ -223,7 +223,11 @@ _GLOBAL(slb_allocate_user)
  */
 slb_finish_load:
         ASM_VSID_SCRAMBLE(r10,r9,256M)
-        rldimi  r11,r10,SLB_VSID_SHIFT,16       /* combine VSID and flags */
+        /*
+         * bits above VSID_BITS_256M need to be ignored from r10
+         * also combine VSID and flags
+         */
+        rldimi  r11,r10,SLB_VSID_SHIFT,(64 - (SLB_VSID_SHIFT + VSID_BITS_256M))
 
         /* r3 = EA, r11 = VSID data */
         /*
@@ -287,7 +291,11 @@ _GLOBAL(slb_compare_rr_to_size)
 slb_finish_load_1T:
         srdi    r10,r10,40-28           /* get 1T ESID */
         ASM_VSID_SCRAMBLE(r10,r9,1T)
-        rldimi  r11,r10,SLB_VSID_SHIFT_1T,16    /* combine VSID and flags */
+        /*
+         * bits above VSID_BITS_1T need to be ignored from r10
+         * also combine VSID and flags
+         */
+        rldimi  r11,r10,SLB_VSID_SHIFT_1T,(64 - (SLB_VSID_SHIFT_1T + VSID_BITS_1T))
         li      r10,MMU_SEGSIZE_1T
         rldimi  r11,r10,SLB_VSID_SSIZE_SHIFT,0  /* insert segment size */