Changes in / [3d4750f:bb6f135] in mainline

Location:

kernel/generic

Files:

• include/macros.h (modified) (1 diff)
• src/mm/km.c (modified) (3 diffs)

kernel/generic/include/macros.h

@@ -69 +69 @@
     uint64_t sz2)
 {
-        uint64_t e1 = s1 + sz1;
-        uint64_t e2 = s2 + sz2;
-        
+        uint64_t e1;
+        uint64_t e2;
+
+        /* Handle the two corner cases when either sz1 or sz2 are zero. */
+        if (sz1 == 0)
+                return (s1 == s2) && (sz2 == 0);
+        e1 = s1 + sz1 - 1;      
+        if (sz2 == 0)
+                return (s1 <= s2) && (s2 <= e1);
+        e2 = s2 + sz2 - 1;
+
+        /* e1 and e2 are end addresses, the sum is imune to overflow */
         return ((s1 <= s2) && (e1 >= e2));
 }

kernel/generic/src/mm/km.c

@@ -134 +134 @@
         ASSERT(ALIGN_UP(size, FRAME_SIZE) == size);
 
+        /* Enforce natural or at least PAGE_SIZE alignment. */
         align = ispwr2(size) ? size : (1U << (fnzb(size) + 1));
         vaddr = km_page_alloc(size, max(PAGE_SIZE, align));
@@ -150 +151 @@
 {
         uintptr_t offs;
+        size_t align;
         ipl_t ipl;
 
@@ -168 +170 @@
         page_table_unlock(AS_KERNEL, true);
 
-        km_page_free(vaddr, size);
+        /*
+         * Match the size parameter with that of km_page_alloc() in
+         * km_map_aligned().
+         */
+        align = ispwr2(size) ? size : (1U << (fnzb(size) + 1));
+        km_page_free(vaddr, max(PAGE_SIZE, align));
 }