[PATCH 2/2] powerpc/64: Increase stack redzone for 64-bit kernel to 512 bytes
From: Bin Meng <hidden>
Date: 2018-09-30 06:22:50
Subsystem:
linux for powerpc (32-bit and 64-bit), ptrace support, the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Oleg Nesterov, Linus Torvalds
commit 573ebfa6601f ("powerpc: Increase stack redzone for 64-bit
userspace to 512 bytes") only changes stack userspace redzone size.
We need increase the kernel one to 512 bytes too per ABIv2 spec.
Signed-off-by: Bin Meng <redacted>
---
arch/powerpc/include/asm/ptrace.h | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index 447cbd1..817be3f 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h@@ -30,16 +30,12 @@ #ifdef __powerpc64__ /* - * Size of redzone that userspace is allowed to use below the stack + * Size of redzone that kernel/userspace is allowed to use below the stack * pointer. This is 288 in the 64-bit big-endian ELF ABI, and 512 in * the new ELFv2 little-endian ABI, so we allow the larger amount. - * - * For kernel code we allow a 288-byte redzone, in order to conserve - * kernel stack space; gcc currently only uses 288 bytes, and will - * hopefully allow explicit control of the redzone size in future. */ #define USER_REDZONE_SIZE 512 -#define KERNEL_REDZONE_SIZE 288 +#define KERNEL_REDZONE_SIZE 512 #define STACK_FRAME_OVERHEAD 112 /* size of minimum stack frame */ #define STACK_FRAME_LR_SAVE 2 /* Location of LR in stack frame */
--
2.7.4