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-rw-r--r--mm/page_poison.c56
1 files changed, 7 insertions, 49 deletions
diff --git a/mm/page_poison.c b/mm/page_poison.c
index ae0482cded87..06ec518b2089 100644
--- a/mm/page_poison.c
+++ b/mm/page_poison.c
@@ -8,45 +8,17 @@
#include <linux/ratelimit.h>
#include <linux/kasan.h>
-static DEFINE_STATIC_KEY_FALSE_RO(want_page_poisoning);
+bool _page_poisoning_enabled_early;
+EXPORT_SYMBOL(_page_poisoning_enabled_early);
+DEFINE_STATIC_KEY_FALSE(_page_poisoning_enabled);
+EXPORT_SYMBOL(_page_poisoning_enabled);
static int __init early_page_poison_param(char *buf)
{
- int ret;
- bool tmp;
-
- ret = strtobool(buf, &tmp);
- if (ret)
- return ret;
-
- if (tmp)
- static_branch_enable(&want_page_poisoning);
- else
- static_branch_disable(&want_page_poisoning);
-
- return 0;
+ return kstrtobool(buf, &_page_poisoning_enabled_early);
}
early_param("page_poison", early_page_poison_param);
-/**
- * page_poisoning_enabled - check if page poisoning is enabled
- *
- * Return true if page poisoning is enabled, or false if not.
- */
-bool page_poisoning_enabled(void)
-{
- /*
- * Assumes that debug_pagealloc_enabled is set before
- * memblock_free_all.
- * Page poisoning is debug page alloc for some arches. If
- * either of those options are enabled, enable poisoning.
- */
- return (static_branch_unlikely(&want_page_poisoning) ||
- (!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) &&
- debug_pagealloc_enabled()));
-}
-EXPORT_SYMBOL_GPL(page_poisoning_enabled);
-
static void poison_page(struct page *page)
{
void *addr = kmap_atomic(page);
@@ -58,7 +30,7 @@ static void poison_page(struct page *page)
kunmap_atomic(addr);
}
-static void poison_pages(struct page *page, int n)
+void __kernel_poison_pages(struct page *page, int n)
{
int i;
@@ -79,9 +51,6 @@ static void check_poison_mem(unsigned char *mem, size_t bytes)
unsigned char *start;
unsigned char *end;
- if (IS_ENABLED(CONFIG_PAGE_POISONING_NO_SANITY))
- return;
-
start = memchr_inv(mem, PAGE_POISON, bytes);
if (!start)
return;
@@ -117,7 +86,7 @@ static void unpoison_page(struct page *page)
kunmap_atomic(addr);
}
-static void unpoison_pages(struct page *page, int n)
+void __kernel_unpoison_pages(struct page *page, int n)
{
int i;
@@ -125,17 +94,6 @@ static void unpoison_pages(struct page *page, int n)
unpoison_page(page + i);
}
-void kernel_poison_pages(struct page *page, int numpages, int enable)
-{
- if (!page_poisoning_enabled())
- return;
-
- if (enable)
- unpoison_pages(page, numpages);
- else
- poison_pages(page, numpages);
-}
-
#ifndef CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC
void __kernel_map_pages(struct page *page, int numpages, int enable)
{