arm64, kfence: enable KFENCE for ARM64

[linux-2.6-microblaze.git] / arch / arm64 / mm / mmu.c

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 25af183..ef7698c 100644 (file)
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1444,16 +1444,19 @@ static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size)
        free_empty_tables(start, end, PAGE_OFFSET, PAGE_END);
 }
 
-static bool inside_linear_region(u64 start, u64 size)
+struct range arch_get_mappable_range(void)
 {
+       struct range mhp_range;
+
        /*
         * Linear mapping region is the range [PAGE_OFFSET..(PAGE_END - 1)]
         * accommodating both its ends but excluding PAGE_END. Max physical
         * range which can be mapped inside this linear mapping range, must
         * also be derived from its end points.
         */
-       return start >= __pa(_PAGE_OFFSET(vabits_actual)) &&
-              (start + size - 1) <= __pa(PAGE_END - 1);
+       mhp_range.start = __pa(_PAGE_OFFSET(vabits_actual));
+       mhp_range.end =  __pa(PAGE_END - 1);
+       return mhp_range;
 }
 
 int arch_add_memory(int nid, u64 start, u64 size,
@@ -1461,12 +1464,14 @@ int arch_add_memory(int nid, u64 start, u64 size,
 {
        int ret, flags = 0;
 
-       if (!inside_linear_region(start, size)) {
-               pr_err("[%llx %llx] is outside linear mapping region\n", start, start + size);
-               return -EINVAL;
-       }
+       VM_BUG_ON(!mhp_range_allowed(start, size, true));
 
-       if (rodata_full || debug_pagealloc_enabled())
+       /*
+        * KFENCE requires linear map to be mapped at page granularity, so that
+        * it is possible to protect/unprotect single pages in the KFENCE pool.
+        */
+       if (rodata_full || debug_pagealloc_enabled() ||
+           IS_ENABLED(CONFIG_KFENCE))
                flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
 
        __create_pgd_mapping(swapper_pg_dir, start, __phys_to_virt(start),