diff options
-rw-r--r-- | arch/arm/mm/init.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 2c2cce9cd8c8..fdc87f9bda55 100644 --- a/arch/arm/mm/init.c +++ b/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) |