KGDB: Notify GDB of machine halt, reboot or power off

Notify GDB of the machine halting, rebooting or powering off by sending it an exited command (remote protocol command 'W'). This is done by calling: void gdbstub_exit(int status) from the arch's machine_{halt,restart,power_off}() functions with an appropriate exit status to be reported to GDB. Signed-off-by: David Howells <dhowells@redhat.com>

KGDB: Notify GDB of machine halt, reboot or power off
Notify GDB of the machine halting, rebooting or powering off by sending it an exited command (remote protocol command 'W'). This is done by calling: void gdbstub_exit(int status) from the arch's machine_{halt,restart,power_off}() functions with an appropriate exit status to be reported to GDB. Signed-off-by: David Howells <dhowells@redhat.com>
David Howells
1 parent e460d64405
Showing 2 changed files with 31 additions and 0 deletions Side-by-side Diff
include/linux/kgdb.h
kernel/debug/gdbstub.c
@@ -297,6 +297,7 @@
 kgdb_handle_exception(int ex_vector, int signo, int err_code,
 		      struct pt_regs *regs);
 extern int kgdb_nmicallback(int cpu, void *regs);
+extern void gdbstub_exit(int status);
  
 extern int			kgdb_single_step;
 extern atomic_t			kgdb_active;
@@ -1093,4 +1093,34 @@
 	put_packet(remcom_out_buffer);
 	return 0;
 }
+
+/**
+ * gdbstub_exit - Send an exit message to GDB
+ * @status: The exit code to report.
+ */
+void gdbstub_exit(int status)
+{
+	unsigned char checksum, ch, buffer[3];
+	int loop;
+
+	buffer[0] = 'W';
+	buffer[1] = hex_asc_hi(status);
+	buffer[2] = hex_asc_lo(status);
+
+	dbg_io_ops->write_char('$');
+	checksum = 0;
+
+	for (loop = 0; loop < 3; loop++) {
+		ch = buffer[loop];
+		checksum += ch;
+		dbg_io_ops->write_char(ch);
+	}
+
+	dbg_io_ops->write_char('#');
+	dbg_io_ops->write_char(hex_asc_hi(checksum));
+	dbg_io_ops->write_char(hex_asc_lo(checksum));
+
+	/* make sure the output is flushed, lest the bootloader clobber it */
+	dbg_io_ops->flush();
+}
...	...	@@ -297,6 +297,7 @@
297	297	kgdb_handle_exception(int ex_vector, int signo, int err_code,
298	298	struct pt_regs *regs);
299	299	extern int kgdb_nmicallback(int cpu, void *regs);
	300	+extern void gdbstub_exit(int status);
300	301
301	302	extern int kgdb_single_step;
302	303	extern atomic_t kgdb_active;
...	...	@@ -1093,4 +1093,34 @@
1093	1093	put_packet(remcom_out_buffer);
1094	1094	return 0;
1095	1095	}
	1096	+
	1097	+/**
	1098	+ * gdbstub_exit - Send an exit message to GDB
	1099	+ * @status: The exit code to report.
	1100	+ */
	1101	+void gdbstub_exit(int status)
	1102	+{
	1103	+ unsigned char checksum, ch, buffer[3];
	1104	+ int loop;
	1105	+
	1106	+ buffer[0] = 'W';
	1107	+ buffer[1] = hex_asc_hi(status);
	1108	+ buffer[2] = hex_asc_lo(status);
	1109	+
	1110	+ dbg_io_ops->write_char('$');
	1111	+ checksum = 0;
	1112	+
	1113	+ for (loop = 0; loop < 3; loop++) {
	1114	+ ch = buffer[loop];
	1115	+ checksum += ch;
	1116	+ dbg_io_ops->write_char(ch);
	1117	+ }
	1118	+
	1119	+ dbg_io_ops->write_char('#');
	1120	+ dbg_io_ops->write_char(hex_asc_hi(checksum));
	1121	+ dbg_io_ops->write_char(hex_asc_lo(checksum));
	1122	+
	1123	+ /* make sure the output is flushed, lest the bootloader clobber it */
	1124	+ dbg_io_ops->flush();
	1125	+}