x86/kasan, mm: Introduce generic kasan_populate_zero_shadow()
Introduce generic kasan_populate_zero_shadow(shadow_start,
shadow_end). This function maps kasan_zero_page to the
[shadow_start, shadow_end] addresses.
This replaces x86_64 specific populate_zero_shadow() and will
be used for ARM64 in follow on patches.
The main changes from original version are:
* Use p?d_populate*() instead of set_p?d()
* Use memblock allocator directly instead of vmemmap_alloc_block()
* __pa() instead of __pa_nodebug(). __pa() causes troubles
iff we use it before kasan_early_init(). kasan_populate_zero_shadow()
will be used later, so we ok with __pa() here.
Signed-off-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Keitel <dkeitel@codeaurora.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yury <yury.norov@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1439444244-26057-3-git-send-email-ryabinin.a.a@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 6fb1c7d..4b9f85c 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -12,8 +12,17 @@
#define KASAN_SHADOW_SCALE_SHIFT 3
#include <asm/kasan.h>
+#include <asm/pgtable.h>
#include <linux/sched.h>
+extern unsigned char kasan_zero_page[PAGE_SIZE];
+extern pte_t kasan_zero_pte[PTRS_PER_PTE];
+extern pmd_t kasan_zero_pmd[PTRS_PER_PMD];
+extern pud_t kasan_zero_pud[PTRS_PER_PUD];
+
+void kasan_populate_zero_shadow(const void *shadow_start,
+ const void *shadow_end);
+
static inline void *kasan_mem_to_shadow(const void *addr)
{
return (void *)((unsigned long)addr >> KASAN_SHADOW_SCALE_SHIFT)