1 files changed, 37 insertions, 10 deletions

diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index c19571c40a21..2fee782077c1 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -212,6 +212,18 @@ static void __init arm_bootmem_init(unsigned long start_pfn,
 }
 
 #ifdef CONFIG_ZONE_DMA
+
+unsigned long arm_dma_zone_size __read_mostly;
+EXPORT_SYMBOL(arm_dma_zone_size);
+
+/*
+ * The DMA mask corresponding to the maximum bus address allocatable
+ * using GFP_DMA.  The default here places no restriction on DMA
+ * allocations.  This must be the smallest DMA mask in the system,
+ * so a successful GFP_DMA allocation will always satisfy this.
+ */
+u32 arm_dma_limit;
+
 static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
         unsigned long dma_size)
 {
@@ -267,17 +279,17 @@ static void __init arm_bootmem_free(unsigned long min, unsigned long max_low,
 #endif
         }
 
-#ifdef ARM_DMA_ZONE_SIZE
-#ifndef CONFIG_ZONE_DMA
-#error ARM_DMA_ZONE_SIZE set but no DMA zone to limit allocations
-#endif
-
+#ifdef CONFIG_ZONE_DMA
         /*
          * Adjust the sizes according to any special requirements for
          * this machine type.
          */
-        arm_adjust_dma_zone(zone_size, zhole_size,
-                ARM_DMA_ZONE_SIZE >> PAGE_SHIFT);
+        if (arm_dma_zone_size) {
+                arm_adjust_dma_zone(zone_size, zhole_size,
+                        arm_dma_zone_size >> PAGE_SHIFT);
+                arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
+        } else
+                arm_dma_limit = 0xffffffff;
 #endif
 
         free_area_init_node(0, zone_size, min, zhole_size);
@@ -422,6 +434,17 @@ static inline int free_area(unsigned long pfn, unsigned long end, char *s)
         return pages;
 }
 
+/*
+ * Poison init memory with an undefined instruction (ARM) or a branch to an
+ * undefined instruction (Thumb).
+ */
+static inline void poison_init_mem(void *s, size_t count)
+{
+        u32 *p = (u32 *)s;
+        while ((count = count - 4))
+                *p++ = 0xe7fddef0;
+}
+
 static inline void
 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
 {
@@ -639,8 +662,8 @@ void __init mem_init(void)
                         "    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 #endif
                         "    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
-                        "      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
                         "      .text : 0x%p" " - 0x%p" "   (%4d kB)\n"
+                        "      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
                         "      .data : 0x%p" " - 0x%p" "   (%4d kB)\n"
                         "       .bss : 0x%p" " - 0x%p" "   (%4d kB)\n",
 
@@ -662,8 +685,8 @@ void __init mem_init(void)
 #endif
                         MLM(MODULES_VADDR, MODULES_END),
 
-                        MLK_ROUNDUP(__init_begin, __init_end),
                         MLK_ROUNDUP(_text, _etext),
+                        MLK_ROUNDUP(__init_begin, __init_end),
                         MLK_ROUNDUP(_sdata, _edata),
                         MLK_ROUNDUP(__bss_start, __bss_stop));
 
@@ -704,11 +727,13 @@ void free_initmem(void)
 #ifdef CONFIG_HAVE_TCM
         extern char __tcm_start, __tcm_end;
 
+        poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
         totalram_pages += free_area(__phys_to_pfn(__pa(&__tcm_start)),
                                     __phys_to_pfn(__pa(&__tcm_end)),
                                     "TCM link");
 #endif
 
+        poison_init_mem(__init_begin, __init_end - __init_begin);
         if (!machine_is_integrator() && !machine_is_cintegrator())
                 totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
                                             __phys_to_pfn(__pa(__init_end)),
@@ -721,10 +746,12 @@ static int keep_initrd;
 
 void free_initrd_mem(unsigned long start, unsigned long end)
 {
-        if (!keep_initrd)
+        if (!keep_initrd) {
+                poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
                 totalram_pages += free_area(__phys_to_pfn(__pa(start)),
                                             __phys_to_pfn(__pa(end)),
                                             "initrd");
+        }
 }
 
 static int __init keepinitrd_setup(char *__unused)