From 864307eb86832d9f1023af860466aba07eae2cd2 Mon Sep 17 00:00:00 2001
From: Stephen Boyd <sboyd@codeaurora.org>
Date: Thu, 7 Jul 2011 18:43:36 +0100
Subject: [PATCH] --- yaml --- r: 258224 b: refs/heads/master c:
 54d525735140e930d87c5afd1b0b3393ffdac021 h: refs/heads/master v: v3

---
 [refs]                   |  2 +-
 trunk/arch/arm/mm/init.c | 17 ++++++++++++++++-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index abd610069ead..84a3edc3431a 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7fa22bd5460bb2021729fa5a1012c60b9b3a56e2
+refs/heads/master: 54d525735140e930d87c5afd1b0b3393ffdac021
diff --git a/trunk/arch/arm/mm/init.c b/trunk/arch/arm/mm/init.c
index 2c2cce9cd8c8..fdc87f9bda55 100644
--- a/trunk/arch/arm/mm/init.c
+++ b/trunk/arch/arm/mm/init.c
@@ -416,6 +416,17 @@ 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)
 {
@@ -696,11 +707,13 @@ 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)),
@@ -713,10 +726,12 @@ 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)