diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/debug.c | 46 | ||||
| -rw-r--r-- | mm/memblock.c | 5 | ||||
| -rw-r--r-- | mm/sparse.c | 4 |
3 files changed, 49 insertions, 6 deletions
diff --git a/mm/debug.c b/mm/debug.c index bd10aad8539a..cdacba12e09a 100644 --- a/mm/debug.c +++ b/mm/debug.c @@ -13,6 +13,7 @@ #include <trace/events/mmflags.h> #include <linux/migrate.h> #include <linux/page_owner.h> +#include <linux/ctype.h> #include "internal.h" @@ -175,4 +176,49 @@ void dump_mm(const struct mm_struct *mm) ); } +static bool page_init_poisoning __read_mostly = true; + +static int __init setup_vm_debug(char *str) +{ + bool __page_init_poisoning = true; + + /* + * Calling vm_debug with no arguments is equivalent to requesting + * to enable all debugging options we can control. + */ + if (*str++ != '=' || !*str) + goto out; + + __page_init_poisoning = false; + if (*str == '-') + goto out; + + while (*str) { + switch (tolower(*str)) { + case'p': + __page_init_poisoning = true; + break; + default: + pr_err("vm_debug option '%c' unknown. skipped\n", + *str); + } + + str++; + } +out: + if (page_init_poisoning && !__page_init_poisoning) + pr_warn("Page struct poisoning disabled by kernel command line option 'vm_debug'\n"); + + page_init_poisoning = __page_init_poisoning; + + return 1; +} +__setup("vm_debug", setup_vm_debug); + +void page_init_poison(struct page *page, size_t size) +{ + if (page_init_poisoning) + memset(page, PAGE_POISON_PATTERN, size); +} +EXPORT_SYMBOL_GPL(page_init_poison); #endif /* CONFIG_DEBUG_VM */ diff --git a/mm/memblock.c b/mm/memblock.c index 237944479d25..a85315083b5a 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -1444,10 +1444,9 @@ void * __init memblock_virt_alloc_try_nid_raw( ptr = memblock_virt_alloc_internal(size, align, min_addr, max_addr, nid); -#ifdef CONFIG_DEBUG_VM if (ptr && size > 0) - memset(ptr, PAGE_POISON_PATTERN, size); -#endif + page_init_poison(ptr, size); + return ptr; } diff --git a/mm/sparse.c b/mm/sparse.c index 10b07eea9a6e..67ad061f7fb8 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -696,13 +696,11 @@ int __meminit sparse_add_one_section(struct pglist_data *pgdat, goto out; } -#ifdef CONFIG_DEBUG_VM /* * Poison uninitialized struct pages in order to catch invalid flags * combinations. */ - memset(memmap, PAGE_POISON_PATTERN, sizeof(struct page) * PAGES_PER_SECTION); -#endif + page_init_poison(memmap, sizeof(struct page) * PAGES_PER_SECTION); section_mark_present(ms); sparse_init_one_section(ms, section_nr, memmap, usemap); |