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-rw-r--r--arch/powerpc/include/asm/compat.h5
-rw-r--r--arch/powerpc/include/asm/ptrace.h16
2 files changed, 18 insertions, 3 deletions
diff --git a/arch/powerpc/include/asm/compat.h b/arch/powerpc/include/asm/compat.h
index 84fdf6857c31..a613d2c82fd9 100644
--- a/arch/powerpc/include/asm/compat.h
+++ b/arch/powerpc/include/asm/compat.h
@@ -200,10 +200,11 @@ static inline void __user *arch_compat_alloc_user_space(long len)
/*
* We can't access below the stack pointer in the 32bit ABI and
- * can access 288 bytes in the 64bit ABI
+ * can access 288 bytes in the 64bit big-endian ABI,
+ * or 512 bytes with the new ELFv2 little-endian ABI.
*/
if (!is_32bit_task())
- usp -= 288;
+ usp -= USER_REDZONE_SIZE;
return (void __user *) (usp - len);
}
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index becc08e6a65c..279b80f3bb29 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -28,11 +28,23 @@
#ifdef __powerpc64__
+/*
+ * Size of redzone that 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 STACK_FRAME_OVERHEAD 112 /* size of minimum stack frame */
#define STACK_FRAME_LR_SAVE 2 /* Location of LR in stack frame */
#define STACK_FRAME_REGS_MARKER ASM_CONST(0x7265677368657265)
#define STACK_INT_FRAME_SIZE (sizeof(struct pt_regs) + \
- STACK_FRAME_OVERHEAD + 288)
+ STACK_FRAME_OVERHEAD + KERNEL_REDZONE_SIZE)
#define STACK_FRAME_MARKER 12
/* Size of dummy stack frame allocated when calling signal handler. */
@@ -41,6 +53,8 @@
#else /* __powerpc64__ */
+#define USER_REDZONE_SIZE 0
+#define KERNEL_REDZONE_SIZE 0
#define STACK_FRAME_OVERHEAD 16 /* size of minimum stack frame */
#define STACK_FRAME_LR_SAVE 1 /* Location of LR in stack frame */
#define STACK_FRAME_REGS_MARKER ASM_CONST(0x72656773)

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