microblaze: Support brki rX, 0x18 for user application debugging
This is the first patch which add support for
user application debugging through brki rX, 0x18 vector.
This patch has side effect which also remove security issue
to use brki rX, 0x18 to freeze kernel.
Support for old gdb support via priviledged exception
(brk r0, r0) is still there. It will be remove in future.
Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/arch/microblaze/kernel/exceptions.c b/arch/microblaze/kernel/exceptions.c
index 02cbdfe..e0c6f8c 100644
--- a/arch/microblaze/kernel/exceptions.c
+++ b/arch/microblaze/kernel/exceptions.c
@@ -48,6 +48,12 @@
do_exit(err);
}
+/* for user application debugging */
+void sw_exception(struct pt_regs *regs)
+{
+ _exception(SIGTRAP, regs, TRAP_BRKPT, regs->r16);
+}
+
void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
{
siginfo_t info;
@@ -143,7 +149,7 @@
#ifdef CONFIG_MMU
case MICROBLAZE_PRIVILEGED_EXCEPTION:
pr_debug(KERN_WARNING "Privileged exception\n");
- /* "brk r0,r0" - used as debug breakpoint */
+ /* "brk r0,r0" - used as debug breakpoint - old toolchain */
if (get_user(code, (unsigned long *)regs->pc) == 0
&& code == 0x980c0000) {
_exception(SIGTRAP, regs, TRAP_BRKPT, addr);