lkml.org 
[lkml]   [2020]   [May]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] powerpc/32: disable KASAN with pages bigger than 16k
Date
Mapping of early shadow area is implemented by using a single static
page table having all entries pointing to the same early shadow page.
The shadow area must therefore occupy full PGD entries.

The shadow area has a size of 128Mbytes starting at 0xf8000000.
With 4k pages, a PGD entry is 4Mbytes
With 16k pages, a PGD entry is 64Mbytes
With 64k pages, a PGD entry is 256Mbytes which is too big.

Until we rework the early shadow mapping, disable KASAN when the
page size is too big.

Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/Kconfig | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 1dfa59126fcf..066b36bf9efa 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -169,8 +169,8 @@ config PPC
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_HUGE_VMAP if PPC_BOOK3S_64 && PPC_RADIX_MMU
select HAVE_ARCH_JUMP_LABEL
- select HAVE_ARCH_KASAN if PPC32
- select HAVE_ARCH_KASAN_VMALLOC if PPC32
+ select HAVE_ARCH_KASAN if PPC32 && PPC_PAGE_SHIFT <= 14
+ select HAVE_ARCH_KASAN_VMALLOC if PPC32 && PPC_PAGE_SHIFT <= 14
select HAVE_ARCH_KGDB
select HAVE_ARCH_MMAP_RND_BITS
select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
--
2.25.0
\
 
 \ /
  Last update: 2020-05-28 12:18    [W:0.078 / U:18.164 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site