[PATCH v7 0/4] KASAN for arm64
From: Suzuki.Poulose@arm.com (Suzuki K. Poulose)
Date: 2015-11-16 11:26:45
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On 13/10/15 09:34, Catalin Marinas wrote:
On Mon, Oct 12, 2015 at 06:52:56PM +0300, Andrey Ryabinin wrote:quoted
Andrey Ryabinin (3): arm64: move PGD_SIZE definition to pgalloc.h arm64: add KASAN support Documentation/features/KASAN: arm64 supports KASAN now Linus Walleij (1): ARM64: kasan: print memory assignmentPatches queued for 4.4. Thanks.
Hi,
I get the following failure with KASAN + 16K_PAGES + 48BIT_VA, with 4.4-rc1:
arch/arm64/mm/kasan_init.c: In function ?kasan_early_init?:
include/linux/compiler.h:484:38: error: call to ?__compiletime_assert_95? declared with attribute error: BUILD_BUG_ON failed: !IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE)
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/compiler.h:467:4: note: in definition of macro ?__compiletime_assert?
prefix ## suffix(); \
^
include/linux/compiler.h:484:2: note: in expansion of macro ?_compiletime_assert?
_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
^
include/linux/bug.h:50:37: note: in expansion of macro ?compiletime_assert?
#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
^
include/linux/bug.h:74:2: note: in expansion of macro ?BUILD_BUG_ON_MSG?
BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
^
arch/arm64/mm/kasan_init.c:95:2: note: in expansion of macro ?BUILD_BUG_ON?
BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE));
---
The problem is that the PGDIR_SIZE is (1UL << 47) with 16K+48bit, which makes
the KASAN_SHADOW_END unaligned(which is aligned to (1UL << (48 - 3)) ). Is the
alignment really needed ? Thoughts on how best we could fix this ?
Cheers
Suzuki