Commit d57f078b193981d1b7d24193f3118c6b806db0ff

Authored by David Howells
1 parent e460d64405

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>

Showing 2 changed files with 31 additions and 0 deletions Side-by-side Diff

include/linux/kgdb.h
... ... @@ -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;
kernel/debug/gdbstub.c
... ... @@ -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 +}