1 // SPDX-License-Identifier: Apache-2.0
5  * debug-trigger listens for an external signal that the BMC is in some way unresponsive. When a
9  * Usage: debug-trigger [SOURCE] [SINK]
12  *  --sink-actions=ACTION
17  *  debug-trigger
18  *	Set the source as stdin, the sink as stdout, and use the default 'sysrq' set of sink
21  *  debug-trigger --sink-actions=sysrq
25  *  debug-trigger /dev/serio_raw0 /proc/sysrq-trigger
26  *	Open /dev/serio_raw0 as the source and /proc/sysrq-trigger as the sink, with the default
28  *	/proc/sysrq-trigger, causing a kernel panic. When 'R' is read from /dev/serio_raw0 'b' will
29  *	be written to /proc/sysrq-trigger, causing an immediate reboot of the system.
31  *  dbug-trigger --sink-actions=dbus /dev/serio_raw0
33  *	read from /dev/serio_raw0 create a dump via phosphor-debug-collector by calling through its
34  *	D-Bus interface, then reboot the system by starting systemd's 'reboot.target'
102 …/* https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/admin-gui…  in sysrq_sink_debug()
108 	if ((rc = write(sysrq->sink, &action, sizeof(action))) == sizeof(action))  in sysrq_sink_debug()
111 	if (rc == -1) {  in sysrq_sink_debug()
121 …/* https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/admin-gui…  in sysrq_sink_reboot()
127 	if ((rc = write(sysrq->sink, &action, sizeof(action))) == sizeof(action))  in sysrq_sink_reboot()
130 	if (rc == -1) {  in sysrq_sink_reboot()
142 	if ((ingress = read(basic->source, op, 1)) != 1) {  in basic_source_poll()
145 			return -errno;  in basic_source_poll()
165 #include <systemd/sd-bus.h>
180 		      strerror(-rc));  in dbus_sink_dump_progress()
209 			      strerror(-rc));  in dbus_sink_dump_progress()
217 				      strerror(-rc));  in dbus_sink_dump_progress()
227 				      strerror(-rc));  in dbus_sink_dump_progress()
236 				      member, strerror(-rc));  in dbus_sink_dump_progress()
254 		sd_bus_slot *slot = sd_bus_get_current_slot(dbus->bus);  in dbus_sink_dump_progress()
273 	rc = sd_bus_call_method(dbus->bus,  in dbus_sink_debug()
281 		warnx("Failed to call CreateDump: %s", strerror(-rc));  in dbus_sink_debug()
288 		warnx("Failed to extract dump object path: %s", strerror(-rc));  in dbus_sink_debug()
293 	rc = sd_bus_match_signal(dbus->bus,  in dbus_sink_debug()
303 		      path, strerror(-rc));  in dbus_sink_debug()
321 		      path, strerror(-rc));  in dbus_sink_debug()
328 	rc = sd_bus_get_property_string(dbus->bus,  in dbus_sink_debug()
337 		      path, strerror(-rc));  in dbus_sink_debug()
366 	rc = sd_bus_call_method(dbus->bus,  in dbus_sink_reboot()
375 				"replace-irreversibly");  in dbus_sink_reboot()
377 		warnx("Failed to start reboot.target: %s", strerror(-rc));  in dbus_sink_reboot()
391 		dbus->pfds[DBUS_SOURCE_PFD_DBUS].fd = sd_bus_get_fd(dbus->bus);  in dbus_source_poll()
392 		dbus->pfds[DBUS_SOURCE_PFD_DBUS].events = sd_bus_get_events(dbus->bus);  in dbus_source_poll()
393 		rc = sd_bus_get_timeout(dbus->bus, &dbusto);  in dbus_source_poll()
399 		} else if (dbus->pfds[DBUS_SOURCE_PFD_DBUS].events == 0) {  in dbus_source_poll()
411 		if ((rc = ppoll(dbus->pfds, ARRAY_SIZE(dbus->pfds), ptsto, NULL)) < 0) {  in dbus_source_poll()
413 			return -errno;  in dbus_source_poll()
416 		if (dbus->pfds[DBUS_SOURCE_PFD_SOURCE].revents) {  in dbus_source_poll()
419 			if ((ingress = read(dbus->pfds[DBUS_SOURCE_PFD_SOURCE].fd, op, 1)) != 1) {  in dbus_source_poll()
422 					return -errno;  in dbus_source_poll()
431 		if (dbus->pfds[DBUS_SOURCE_PFD_DBUS].revents) {  in dbus_source_poll()
432 			if ((rc = sd_bus_process(dbus->bus, NULL)) < 0) {  in dbus_source_poll()
433 				warnx("Failed processing inbound D-Bus messages: %s",  in dbus_source_poll()
434 				      strerror(-rc));  in dbus_source_poll()
471 	while (!(rc = source->ops->poll(source->ctx, &command))) {  in process()
475 			sink->ops->debug(sink->ctx);  in process()
479 			sink->ops->reboot(sink->ctx);  in process()
481 		default:  in process()
487 		warnx("Failed to poll source: %s", strerror(-rc));  in process()
509 			{"sink-actions", required_argument, 0, 's'},  in main()
515 		if (c == -1)  in main()
522 		default:  in main()
528 	 * The default behaviour sets the source file descriptor as stdin and the sink file  in main()
529 	 * descriptor as stdout. This allows trivial testing on the command-line with just a  in main()
545 		devpath[PATH_MAX - 1] = '\0';  in main()
549 		strncat(devnode, devid, sizeof(devnode) - strlen("/dev/"));  in main()
550 		devnode[PATH_MAX - 1] = '\0';  in main()
552 		if ((sourcefd = open(devnode, O_RDONLY)) == -1)  in main()
560 	 * --sink-actions option, then default to 'sysrq'. Otherwise, if --sink-actions=sysrq has  in main()
569 			if ((sinkfd = open(argv[optind], O_WRONLY)) == -1)  in main()
584 	/* Set up the dbus sink actions if requested via --sink-actions=dbus */  in main()
592 			       strerror(-rc));  in main()
606 	/* Check we're done with the command-line */  in main()
608 		errx(EXIT_FAILURE, "Found %d unexpected arguments", argc - optind);  in main()
616 	/* Trigger the actions on the sink when we receive an event from the source */  in main()