1 files changed, 22 insertions, 12 deletions

diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
index 564fff06f5c1..23ec2c5e3b78 100644
--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -122,7 +122,8 @@ static int slice_high_has_vma(struct mm_struct *mm, unsigned long slice)
         return !slice_area_is_free(mm, start, end - start);
 }
 
-static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret)
+static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
+                                unsigned long high_limit)
 {
         unsigned long i;
 
@@ -133,15 +134,16 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret)
                 if (!slice_low_has_vma(mm, i))
                         ret->low_slices |= 1u << i;
 
-        if (mm->context.slb_addr_limit <= SLICE_LOW_TOP)
+        if (high_limit <= SLICE_LOW_TOP)
                 return;
 
-        for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit); i++)
+        for (i = 0; i < GET_HIGH_SLICE_INDEX(high_limit); i++)
                 if (!slice_high_has_vma(mm, i))
                         __set_bit(i, ret->high_slices);
 }
 
-static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_mask *ret)
+static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_mask *ret,
+                                unsigned long high_limit)
 {
         unsigned char *hpsizes;
         int index, mask_index;
@@ -156,8 +158,11 @@ static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_ma
                 if (((lpsizes >> (i * 4)) & 0xf) == psize)
                         ret->low_slices |= 1u << i;
 
+        if (high_limit <= SLICE_LOW_TOP)
+                return;
+
         hpsizes = mm->context.high_slices_psize;
-        for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit); i++) {
+        for (i = 0; i < GET_HIGH_SLICE_INDEX(high_limit); i++) {
                 mask_index = i & 0x1;
                 index = i >> 1;
                 if (((hpsizes[index] >> (mask_index * 4)) & 0xf) == psize)
@@ -169,6 +174,10 @@ static int slice_check_fit(struct mm_struct *mm,
                            struct slice_mask mask, struct slice_mask available)
 {
         DECLARE_BITMAP(result, SLICE_NUM_HIGH);
+        /*
+         * Make sure we just do bit compare only to the max
+         * addr limit and not the full bit map size.
+         */
         unsigned long slice_count = GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit);
 
         bitmap_and(result, mask.high_slices,
@@ -472,7 +481,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
         /* First make up a "good" mask of slices that have the right size
          * already
          */
-        slice_mask_for_size(mm, psize, &good_mask);
+        slice_mask_for_size(mm, psize, &good_mask, high_limit);
         slice_print_mask(" good_mask", good_mask);
 
         /*
@@ -497,7 +506,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
 #ifdef CONFIG_PPC_64K_PAGES
         /* If we support combo pages, we can allow 64k pages in 4k slices */
         if (psize == MMU_PAGE_64K) {
-                slice_mask_for_size(mm, MMU_PAGE_4K, &compat_mask);
+                slice_mask_for_size(mm, MMU_PAGE_4K, &compat_mask, high_limit);
                 if (fixed)
                         slice_or_mask(&good_mask, &compat_mask);
         }
@@ -530,11 +539,11 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
                         return newaddr;
                 }
         }
-
-        /* We don't fit in the good mask, check what other slices are
+        /*
+         * We don't fit in the good mask, check what other slices are
          * empty and thus can be converted
          */
-        slice_mask_for_free(mm, &potential_mask);
+        slice_mask_for_free(mm, &potential_mask, high_limit);
         slice_or_mask(&potential_mask, &good_mask);
         slice_print_mask(" potential", potential_mask);
 
@@ -744,17 +753,18 @@ int is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
 {
         struct slice_mask mask, available;
         unsigned int psize = mm->context.user_psize;
+        unsigned long high_limit = mm->context.slb_addr_limit;
 
         if (radix_enabled())
                 return 0;
 
         slice_range_to_mask(addr, len, &mask);
-        slice_mask_for_size(mm, psize, &available);
+        slice_mask_for_size(mm, psize, &available, high_limit);
 #ifdef CONFIG_PPC_64K_PAGES
         /* We need to account for 4k slices too */
         if (psize == MMU_PAGE_64K) {
                 struct slice_mask compat_mask;
-                slice_mask_for_size(mm, MMU_PAGE_4K, &compat_mask);
+                slice_mask_for_size(mm, MMU_PAGE_4K, &compat_mask, high_limit);
                 slice_or_mask(&available, &compat_mask);
         }
 #endif