[src/trunk]: src/sys/arch/arm/include PR/52867: Martin Husemann: arm sofware ...

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5084b01627c4
branches:  trunk
changeset: 358396:5084b01627c4
user:      christos <christos%NetBSD.org@localhost>
date:      Wed Dec 27 19:35:05 2017 +0000

description:
PR/52867: Martin Husemann: arm sofware breakpoint asm is slightly off

ARM uses an undefined instruction to emulate a software breakpoint.
However, the ptrace.h instruction on the one hand, and gdb/the kernel
disagree on the exact value.

This causes PTRACE_BREAKPOINT_ASM to generate a SIGILL instead of a SIGTRAP.

diffstat:

 sys/arch/arm/include/ptrace.h |  11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

diffs (24 lines):

diff -r 48ee32cb51b5 -r 5084b01627c4 sys/arch/arm/include/ptrace.h
--- a/sys/arch/arm/include/ptrace.h     Wed Dec 27 19:20:41 2017 +0000
+++ b/sys/arch/arm/include/ptrace.h     Wed Dec 27 19:35:05 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ptrace.h,v 1.11 2017/04/12 18:17:59 kamil Exp $        */
+/*     $NetBSD: ptrace.h,v 1.12 2017/12/27 19:35:05 christos Exp $     */
 
 /*
  * Copyright (c) 1995 Frank Lancaster
@@ -64,7 +64,12 @@
 #define PTRACE_REG_SP(_r)              (_r)->r_sp
 #define PTRACE_REG_INTRV(_r)           (_r)->r[0]
 
-#define PTRACE_BREAKPOINT      ((const uint8_t[]) { 0xe7, 0xff, 0xff, 0xfe })
-#define PTRACE_BREAKPOINT_INSN 0xe7fffffe
+#ifdef __ARMEB__
+#define PTRACE_BREAKPOINT      ((const uint8_t[]) { 0xfe, 0xde, 0xff, 0xe7 })
+#define PTRACE_BREAKPOINT_INSN 0xfedeffe7
+#else
+#define PTRACE_BREAKPOINT      ((const uint8_t[]) { 0xe7, 0xff, 0xde, 0xfe })
+#define PTRACE_BREAKPOINT_INSN 0xe7ffdefe
+#endif
 #define PTRACE_BREAKPOINT_ASM  __asm __volatile (".word " ___STRING(PTRACE_BREAKPOINT_INSN) )
 #define PTRACE_BREAKPOINT_SIZE 4