summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--arch/mn10300/Kconfig.debug8
-rw-r--r--arch/mn10300/kernel/gdb-stub.c12
2 files changed, 18 insertions, 2 deletions
diff --git a/arch/mn10300/Kconfig.debug b/arch/mn10300/Kconfig.debug
index ce83c74b3fd7..a1b8620f65ae 100644
--- a/arch/mn10300/Kconfig.debug
+++ b/arch/mn10300/Kconfig.debug
@@ -54,6 +54,14 @@ config GDBSTUB_IMMEDIATE
possible, leaving the program counter at the beginning of
start_kernel() in init/main.c.
+config GDBSTUB_ALLOW_SINGLE_STEP
+ bool "Allow software single-stepping in GDB stub"
+ depends on GDBSTUB && !SMP && !PREEMPT
+ help
+ Allow GDB stub to perform software single-stepping through the
+ kernel. This doesn't work very well on SMP or preemptible kernels as
+ it uses temporary breakpoints to emulate single-stepping.
+
config GDB_CONSOLE
bool "Console output to GDB"
depends on GDBSTUB
diff --git a/arch/mn10300/kernel/gdb-stub.c b/arch/mn10300/kernel/gdb-stub.c
index b169d99d9f20..a9c1e916687f 100644
--- a/arch/mn10300/kernel/gdb-stub.c
+++ b/arch/mn10300/kernel/gdb-stub.c
@@ -405,6 +405,7 @@ static int hexToInt(char **ptr, int *intValue)
return (numChars);
}
+#ifdef CONFIG_GDBSTUB_ALLOW_SINGLE_STEP
/*
* We single-step by setting breakpoints. When an exception
* is handled, we need to restore the instructions hoisted
@@ -729,6 +730,7 @@ static int gdbstub_single_step(struct pt_regs *regs)
__gdbstub_restore_bp();
return -EFAULT;
}
+#endif /* CONFIG_GDBSTUB_ALLOW_SINGLE_STEP */
#ifdef CONFIG_GDBSTUB_CONSOLE
@@ -1208,11 +1210,13 @@ static int gdbstub(struct pt_regs *regs, enum exception_code excep)
/* if we were single stepping, restore the opcodes hoisted for the
* breakpoint[s] */
broke = 0;
+#ifdef CONFIG_GDBSTUB_ALLOW_SINGLE_STEP
if ((step_bp[0].addr && step_bp[0].addr == (u8 *) regs->pc) ||
(step_bp[1].addr && step_bp[1].addr == (u8 *) regs->pc))
broke = 1;
__gdbstub_restore_bp();
+#endif
if (gdbstub_rx_unget) {
sigval = SIGINT;
@@ -1548,17 +1552,21 @@ packet_waiting:
* Step to next instruction
*/
case 's':
- /*
- * using the T flag doesn't seem to perform single
+ /* Using the T flag doesn't seem to perform single
* stepping (it seems to wind up being caught by the
* JTAG unit), so we have to use breakpoints and
* continue instead.
*/
+#ifdef CONFIG_GDBSTUB_ALLOW_SINGLE_STEP
if (gdbstub_single_step(regs) < 0)
/* ignore any fault error for now */
gdbstub_printk("unable to set single-step"
" bp\n");
goto done;
+#else
+ gdbstub_strcpy(output_buffer, "E01");
+ break;
+#endif
/*
* Set baud rate (bBB)
OpenPOWER on IntegriCloud