xref: /kvmtool/builtin-run.c (revision 76f073fcf862a709e9827b2d91a815bd407aa92a)
1 #include "kvm/builtin-run.h"
2 
3 #include "kvm/builtin-setup.h"
4 #include "kvm/virtio-balloon.h"
5 #include "kvm/virtio-console.h"
6 #include "kvm/parse-options.h"
7 #include "kvm/8250-serial.h"
8 #include "kvm/framebuffer.h"
9 #include "kvm/disk-image.h"
10 #include "kvm/threadpool.h"
11 #include "kvm/virtio-scsi.h"
12 #include "kvm/virtio-blk.h"
13 #include "kvm/virtio-net.h"
14 #include "kvm/virtio-rng.h"
15 #include "kvm/ioeventfd.h"
16 #include "kvm/virtio-9p.h"
17 #include "kvm/barrier.h"
18 #include "kvm/kvm-cpu.h"
19 #include "kvm/ioport.h"
20 #include "kvm/symbol.h"
21 #include "kvm/i8042.h"
22 #include "kvm/mutex.h"
23 #include "kvm/term.h"
24 #include "kvm/util.h"
25 #include "kvm/strbuf.h"
26 #include "kvm/vesa.h"
27 #include "kvm/irq.h"
28 #include "kvm/kvm.h"
29 #include "kvm/pci.h"
30 #include "kvm/rtc.h"
31 #include "kvm/sdl.h"
32 #include "kvm/vnc.h"
33 #include "kvm/guest_compat.h"
34 #include "kvm/pci-shmem.h"
35 #include "kvm/kvm-ipc.h"
36 #include "kvm/builtin-debug.h"
37 
38 #include <linux/types.h>
39 #include <linux/err.h>
40 
41 #include <sys/utsname.h>
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 #include <termios.h>
45 #include <signal.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 #include <ctype.h>
50 #include <stdio.h>
51 
52 #define MB_SHIFT		(20)
53 #define KB_SHIFT		(10)
54 #define GB_SHIFT		(30)
55 
56 __thread struct kvm_cpu *current_kvm_cpu;
57 
58 static int  kvm_run_wrapper;
59 
60 bool do_debug_print = false;
61 
62 extern char _binary_guest_init_start;
63 extern char _binary_guest_init_size;
64 
65 static const char * const run_usage[] = {
66 	"lkvm run [<options>] [<kernel image>]",
67 	NULL
68 };
69 
70 enum {
71 	KVM_RUN_DEFAULT,
72 	KVM_RUN_SANDBOX,
73 };
74 
75 static int img_name_parser(const struct option *opt, const char *arg, int unset)
76 {
77 	char path[PATH_MAX];
78 	struct stat st;
79 
80 	snprintf(path, PATH_MAX, "%s%s", kvm__get_dir(), arg);
81 
82 	if ((stat(arg, &st) == 0 && S_ISDIR(st.st_mode)) ||
83 	   (stat(path, &st) == 0 && S_ISDIR(st.st_mode)))
84 		return virtio_9p_img_name_parser(opt, arg, unset);
85 	return disk_img_name_parser(opt, arg, unset);
86 }
87 
88 void kvm_run_set_wrapper_sandbox(void)
89 {
90 	kvm_run_wrapper = KVM_RUN_SANDBOX;
91 }
92 
93 #ifndef OPT_ARCH_RUN
94 #define OPT_ARCH_RUN(...)
95 #endif
96 
97 #define BUILD_OPTIONS(name, cfg, kvm)					\
98 	struct option name[] = {					\
99 	OPT_GROUP("Basic options:"),					\
100 	OPT_STRING('\0', "name", &(cfg)->guest_name, "guest name",	\
101 			"A name for the guest"),			\
102 	OPT_INTEGER('c', "cpus", &(cfg)->nrcpus, "Number of CPUs"),	\
103 	OPT_U64('m', "mem", &(cfg)->ram_size, "Virtual machine memory"	\
104 		" size in MiB."),					\
105 	OPT_CALLBACK('\0', "shmem", NULL,				\
106 		     "[pci:]<addr>:<size>[:handle=<handle>][:create]",	\
107 		     "Share host shmem with guest via pci device",	\
108 		     shmem_parser, NULL),				\
109 	OPT_CALLBACK('d', "disk", kvm, "image or rootfs_dir", "Disk "	\
110 			" image or rootfs directory", img_name_parser,	\
111 			kvm),						\
112 	OPT_BOOLEAN('\0', "balloon", &(cfg)->balloon, "Enable virtio"	\
113 			" balloon"),					\
114 	OPT_BOOLEAN('\0', "vnc", &(cfg)->vnc, "Enable VNC framebuffer"),\
115 	OPT_BOOLEAN('\0', "gtk", &(cfg)->gtk, "Enable GTK framebuffer"),\
116 	OPT_BOOLEAN('\0', "sdl", &(cfg)->sdl, "Enable SDL framebuffer"),\
117 	OPT_BOOLEAN('\0', "rng", &(cfg)->virtio_rng, "Enable virtio"	\
118 			" Random Number Generator"),			\
119 	OPT_CALLBACK('\0', "9p", NULL, "dir_to_share,tag_name",		\
120 		     "Enable virtio 9p to share files between host and"	\
121 		     " guest", virtio_9p_rootdir_parser, kvm),		\
122 	OPT_STRING('\0', "console", &(cfg)->console, "serial, virtio or"\
123 			" hv", "Console to use"),			\
124 	OPT_STRING('\0', "dev", &(cfg)->dev, "device_file",		\
125 			"KVM device file"),				\
126 	OPT_CALLBACK('\0', "tty", NULL, "tty id",			\
127 		     "Remap guest TTY into a pty on the host",		\
128 		     tty_parser, NULL),					\
129 	OPT_STRING('\0', "sandbox", &(cfg)->sandbox, "script",		\
130 			"Run this script when booting into custom"	\
131 			" rootfs"),					\
132 	OPT_STRING('\0', "hugetlbfs", &(cfg)->hugetlbfs_path, "path",	\
133 			"Hugetlbfs path"),				\
134 									\
135 	OPT_GROUP("Kernel options:"),					\
136 	OPT_STRING('k', "kernel", &(cfg)->kernel_filename, "kernel",	\
137 			"Kernel to boot in virtual machine"),		\
138 	OPT_STRING('i', "initrd", &(cfg)->initrd_filename, "initrd",	\
139 			"Initial RAM disk image"),			\
140 	OPT_STRING('p', "params", &(cfg)->kernel_cmdline, "params",	\
141 			"Kernel command line arguments"),		\
142 	OPT_STRING('f', "firmware", &(cfg)->firmware_filename, "firmware",\
143 			"Firmware image to boot in virtual machine"),	\
144 									\
145 	OPT_GROUP("Networking options:"),				\
146 	OPT_CALLBACK_DEFAULT('n', "network", NULL, "network params",	\
147 		     "Create a new guest NIC",				\
148 		     netdev_parser, NULL, kvm),				\
149 	OPT_BOOLEAN('\0', "no-dhcp", &(cfg)->no_dhcp, "Disable kernel"	\
150 			" DHCP in rootfs mode"),			\
151 									\
152 	OPT_GROUP("Debug options:"),					\
153 	OPT_BOOLEAN('\0', "debug", &do_debug_print,			\
154 			"Enable debug messages"),			\
155 	OPT_BOOLEAN('\0', "debug-single-step", &(cfg)->single_step,	\
156 			"Enable single stepping"),			\
157 	OPT_BOOLEAN('\0', "debug-ioport", &(cfg)->ioport_debug,		\
158 			"Enable ioport debugging"),			\
159 	OPT_BOOLEAN('\0', "debug-mmio", &(cfg)->mmio_debug,		\
160 			"Enable MMIO debugging"),			\
161 	OPT_INTEGER('\0', "debug-iodelay", &(cfg)->debug_iodelay,	\
162 			"Delay IO by millisecond"),			\
163 									\
164 	OPT_ARCH(RUN, cfg)						\
165 	OPT_END()							\
166 	};
167 
168 static void handle_sigalrm(int sig, siginfo_t *si, void *uc)
169 {
170 	struct kvm *kvm = si->si_value.sival_ptr;
171 
172 	kvm__arch_periodic_poll(kvm);
173 }
174 
175 static void *kvm_cpu_thread(void *arg)
176 {
177 	char name[16];
178 
179 	current_kvm_cpu = arg;
180 
181 	sprintf(name, "kvm-vcpu-%lu", current_kvm_cpu->cpu_id);
182 	kvm__set_thread_name(name);
183 
184 	if (kvm_cpu__start(current_kvm_cpu))
185 		goto panic_kvm;
186 
187 	return (void *) (intptr_t) 0;
188 
189 panic_kvm:
190 	fprintf(stderr, "KVM exit reason: %u (\"%s\")\n",
191 		current_kvm_cpu->kvm_run->exit_reason,
192 		kvm_exit_reasons[current_kvm_cpu->kvm_run->exit_reason]);
193 	if (current_kvm_cpu->kvm_run->exit_reason == KVM_EXIT_UNKNOWN)
194 		fprintf(stderr, "KVM exit code: 0x%Lu\n",
195 			current_kvm_cpu->kvm_run->hw.hardware_exit_reason);
196 
197 	kvm_cpu__set_debug_fd(STDOUT_FILENO);
198 	kvm_cpu__show_registers(current_kvm_cpu);
199 	kvm_cpu__show_code(current_kvm_cpu);
200 	kvm_cpu__show_page_tables(current_kvm_cpu);
201 
202 	return (void *) (intptr_t) 1;
203 }
204 
205 static char kernel[PATH_MAX];
206 
207 static const char *host_kernels[] = {
208 	"/boot/vmlinuz",
209 	"/boot/bzImage",
210 	NULL
211 };
212 
213 static const char *default_kernels[] = {
214 	"./bzImage",
215 	"arch/" BUILD_ARCH "/boot/bzImage",
216 	"../../arch/" BUILD_ARCH "/boot/bzImage",
217 	NULL
218 };
219 
220 static const char *default_vmlinux[] = {
221 	"vmlinux",
222 	"../../../vmlinux",
223 	"../../vmlinux",
224 	NULL
225 };
226 
227 static void kernel_usage_with_options(void)
228 {
229 	const char **k;
230 	struct utsname uts;
231 
232 	fprintf(stderr, "Fatal: could not find default kernel image in:\n");
233 	k = &default_kernels[0];
234 	while (*k) {
235 		fprintf(stderr, "\t%s\n", *k);
236 		k++;
237 	}
238 
239 	if (uname(&uts) < 0)
240 		return;
241 
242 	k = &host_kernels[0];
243 	while (*k) {
244 		if (snprintf(kernel, PATH_MAX, "%s-%s", *k, uts.release) < 0)
245 			return;
246 		fprintf(stderr, "\t%s\n", kernel);
247 		k++;
248 	}
249 	fprintf(stderr, "\nPlease see '%s run --help' for more options.\n\n",
250 		KVM_BINARY_NAME);
251 }
252 
253 static u64 host_ram_size(void)
254 {
255 	long page_size;
256 	long nr_pages;
257 
258 	nr_pages	= sysconf(_SC_PHYS_PAGES);
259 	if (nr_pages < 0) {
260 		pr_warning("sysconf(_SC_PHYS_PAGES) failed");
261 		return 0;
262 	}
263 
264 	page_size	= sysconf(_SC_PAGE_SIZE);
265 	if (page_size < 0) {
266 		pr_warning("sysconf(_SC_PAGE_SIZE) failed");
267 		return 0;
268 	}
269 
270 	return (nr_pages * page_size) >> MB_SHIFT;
271 }
272 
273 /*
274  * If user didn't specify how much memory it wants to allocate for the guest,
275  * avoid filling the whole host RAM.
276  */
277 #define RAM_SIZE_RATIO		0.8
278 
279 static u64 get_ram_size(int nr_cpus)
280 {
281 	u64 available;
282 	u64 ram_size;
283 
284 	ram_size	= 64 * (nr_cpus + 3);
285 
286 	available	= host_ram_size() * RAM_SIZE_RATIO;
287 	if (!available)
288 		available = MIN_RAM_SIZE_MB;
289 
290 	if (ram_size > available)
291 		ram_size	= available;
292 
293 	return ram_size;
294 }
295 
296 static const char *find_kernel(void)
297 {
298 	const char **k;
299 	struct stat st;
300 	struct utsname uts;
301 
302 	k = &default_kernels[0];
303 	while (*k) {
304 		if (stat(*k, &st) < 0 || !S_ISREG(st.st_mode)) {
305 			k++;
306 			continue;
307 		}
308 		strncpy(kernel, *k, PATH_MAX);
309 		return kernel;
310 	}
311 
312 	if (uname(&uts) < 0)
313 		return NULL;
314 
315 	k = &host_kernels[0];
316 	while (*k) {
317 		if (snprintf(kernel, PATH_MAX, "%s-%s", *k, uts.release) < 0)
318 			return NULL;
319 
320 		if (stat(kernel, &st) < 0 || !S_ISREG(st.st_mode)) {
321 			k++;
322 			continue;
323 		}
324 		return kernel;
325 
326 	}
327 	return NULL;
328 }
329 
330 static const char *find_vmlinux(void)
331 {
332 	const char **vmlinux;
333 
334 	vmlinux = &default_vmlinux[0];
335 	while (*vmlinux) {
336 		struct stat st;
337 
338 		if (stat(*vmlinux, &st) < 0 || !S_ISREG(st.st_mode)) {
339 			vmlinux++;
340 			continue;
341 		}
342 		return *vmlinux;
343 	}
344 	return NULL;
345 }
346 
347 void kvm_run_help(void)
348 {
349 	struct kvm *kvm = NULL;
350 
351 	BUILD_OPTIONS(options, &kvm->cfg, kvm);
352 	usage_with_options(run_usage, options);
353 }
354 
355 static int kvm_setup_guest_init(struct kvm *kvm)
356 {
357 	const char *rootfs = kvm->cfg.custom_rootfs_name;
358 	char tmp[PATH_MAX];
359 	size_t size;
360 	int fd, ret;
361 	char *data;
362 
363 	/* Setup /virt/init */
364 	size = (size_t)&_binary_guest_init_size;
365 	data = (char *)&_binary_guest_init_start;
366 	snprintf(tmp, PATH_MAX, "%s%s/virt/init", kvm__get_dir(), rootfs);
367 	remove(tmp);
368 	fd = open(tmp, O_CREAT | O_WRONLY, 0755);
369 	if (fd < 0)
370 		die("Fail to setup %s", tmp);
371 	ret = xwrite(fd, data, size);
372 	if (ret < 0)
373 		die("Fail to setup %s", tmp);
374 	close(fd);
375 
376 	return 0;
377 }
378 
379 static int kvm_run_set_sandbox(struct kvm *kvm)
380 {
381 	const char *guestfs_name = kvm->cfg.custom_rootfs_name;
382 	char path[PATH_MAX], script[PATH_MAX], *tmp;
383 
384 	snprintf(path, PATH_MAX, "%s%s/virt/sandbox.sh", kvm__get_dir(), guestfs_name);
385 
386 	remove(path);
387 
388 	if (kvm->cfg.sandbox == NULL)
389 		return 0;
390 
391 	tmp = realpath(kvm->cfg.sandbox, NULL);
392 	if (tmp == NULL)
393 		return -ENOMEM;
394 
395 	snprintf(script, PATH_MAX, "/host/%s", tmp);
396 	free(tmp);
397 
398 	return symlink(script, path);
399 }
400 
401 static void kvm_write_sandbox_cmd_exactly(int fd, const char *arg)
402 {
403 	const char *single_quote;
404 
405 	if (!*arg) { /* zero length string */
406 		if (write(fd, "''", 2) <= 0)
407 			die("Failed writing sandbox script");
408 		return;
409 	}
410 
411 	while (*arg) {
412 		single_quote = strchrnul(arg, '\'');
413 
414 		/* write non-single-quote string as #('string') */
415 		if (arg != single_quote) {
416 			if (write(fd, "'", 1) <= 0 ||
417 			    write(fd, arg, single_quote - arg) <= 0 ||
418 			    write(fd, "'", 1) <= 0)
419 				die("Failed writing sandbox script");
420 		}
421 
422 		/* write single quote as #("'") */
423 		if (*single_quote) {
424 			if (write(fd, "\"'\"", 3) <= 0)
425 				die("Failed writing sandbox script");
426 		} else
427 			break;
428 
429 		arg = single_quote + 1;
430 	}
431 }
432 
433 static void resolve_program(const char *src, char *dst, size_t len)
434 {
435 	struct stat st;
436 	int err;
437 
438 	err = stat(src, &st);
439 
440 	if (!err && S_ISREG(st.st_mode)) {
441 		char resolved_path[PATH_MAX];
442 
443 		if (!realpath(src, resolved_path))
444 			die("Unable to resolve program %s: %s\n", src, strerror(errno));
445 
446 		snprintf(dst, len, "/host%s", resolved_path);
447 	} else
448 		strncpy(dst, src, len);
449 }
450 
451 static void kvm_run_write_sandbox_cmd(struct kvm *kvm, const char **argv, int argc)
452 {
453 	const char script_hdr[] = "#! /bin/bash\n\n";
454 	char program[PATH_MAX];
455 	int fd;
456 
457 	remove(kvm->cfg.sandbox);
458 
459 	fd = open(kvm->cfg.sandbox, O_RDWR | O_CREAT, 0777);
460 	if (fd < 0)
461 		die("Failed creating sandbox script");
462 
463 	if (write(fd, script_hdr, sizeof(script_hdr) - 1) <= 0)
464 		die("Failed writing sandbox script");
465 
466 	resolve_program(argv[0], program, PATH_MAX);
467 	kvm_write_sandbox_cmd_exactly(fd, program);
468 
469 	argv++;
470 	argc--;
471 
472 	while (argc) {
473 		if (write(fd, " ", 1) <= 0)
474 			die("Failed writing sandbox script");
475 
476 		kvm_write_sandbox_cmd_exactly(fd, argv[0]);
477 		argv++;
478 		argc--;
479 	}
480 	if (write(fd, "\n", 1) <= 0)
481 		die("Failed writing sandbox script");
482 
483 	close(fd);
484 }
485 
486 static struct kvm *kvm_cmd_run_init(int argc, const char **argv)
487 {
488 	static char real_cmdline[2048], default_name[20];
489 	unsigned int nr_online_cpus;
490 	struct sigaction sa;
491 	struct kvm *kvm = kvm__new();
492 
493 	if (IS_ERR(kvm))
494 		return kvm;
495 
496 	sa.sa_flags = SA_SIGINFO;
497 	sa.sa_sigaction = handle_sigalrm;
498 	sigemptyset(&sa.sa_mask);
499 	sigaction(SIGALRM, &sa, NULL);
500 
501 	nr_online_cpus = sysconf(_SC_NPROCESSORS_ONLN);
502 	kvm->cfg.custom_rootfs_name = "default";
503 
504 	while (argc != 0) {
505 		BUILD_OPTIONS(options, &kvm->cfg, kvm);
506 		argc = parse_options(argc, argv, options, run_usage,
507 				PARSE_OPT_STOP_AT_NON_OPTION |
508 				PARSE_OPT_KEEP_DASHDASH);
509 		if (argc != 0) {
510 			/* Cusrom options, should have been handled elsewhere */
511 			if (strcmp(argv[0], "--") == 0) {
512 				if (kvm_run_wrapper == KVM_RUN_SANDBOX) {
513 					kvm->cfg.sandbox = DEFAULT_SANDBOX_FILENAME;
514 					kvm_run_write_sandbox_cmd(kvm, argv+1, argc-1);
515 					break;
516 				}
517 			}
518 
519 			if ((kvm_run_wrapper == KVM_RUN_DEFAULT && kvm->cfg.kernel_filename) ||
520 				(kvm_run_wrapper == KVM_RUN_SANDBOX && kvm->cfg.sandbox)) {
521 				fprintf(stderr, "Cannot handle parameter: "
522 						"%s\n", argv[0]);
523 				usage_with_options(run_usage, options);
524 				free(kvm);
525 				return ERR_PTR(-EINVAL);
526 			}
527 			if (kvm_run_wrapper == KVM_RUN_SANDBOX) {
528 				/*
529 				 * first unhandled parameter is treated as
530 				 * sandbox command
531 				 */
532 				kvm->cfg.sandbox = DEFAULT_SANDBOX_FILENAME;
533 				kvm_run_write_sandbox_cmd(kvm, argv, argc);
534 			} else {
535 				/*
536 				 * first unhandled parameter is treated as a kernel
537 				 * image
538 				 */
539 				kvm->cfg.kernel_filename = argv[0];
540 			}
541 			argv++;
542 			argc--;
543 		}
544 
545 	}
546 
547 	kvm->nr_disks = kvm->cfg.image_count;
548 
549 	if (!kvm->cfg.kernel_filename)
550 		kvm->cfg.kernel_filename = find_kernel();
551 
552 	if (!kvm->cfg.kernel_filename) {
553 		kernel_usage_with_options();
554 		return ERR_PTR(-EINVAL);
555 	}
556 
557 	kvm->cfg.vmlinux_filename = find_vmlinux();
558 	kvm->vmlinux = kvm->cfg.vmlinux_filename;
559 
560 	if (kvm->cfg.nrcpus == 0)
561 		kvm->cfg.nrcpus = nr_online_cpus;
562 
563 	if (!kvm->cfg.ram_size)
564 		kvm->cfg.ram_size = get_ram_size(kvm->cfg.nrcpus);
565 
566 	if (kvm->cfg.ram_size > host_ram_size())
567 		pr_warning("Guest memory size %lluMB exceeds host physical RAM size %lluMB", kvm->cfg.ram_size, host_ram_size());
568 
569 	kvm->cfg.ram_size <<= MB_SHIFT;
570 
571 	if (!kvm->cfg.dev)
572 		kvm->cfg.dev = DEFAULT_KVM_DEV;
573 
574 	if (!kvm->cfg.console)
575 		kvm->cfg.console = DEFAULT_CONSOLE;
576 
577 	if (!strncmp(kvm->cfg.console, "virtio", 6))
578 		kvm->cfg.active_console  = CONSOLE_VIRTIO;
579 	else if (!strncmp(kvm->cfg.console, "serial", 6))
580 		kvm->cfg.active_console  = CONSOLE_8250;
581 	else if (!strncmp(kvm->cfg.console, "hv", 2))
582 		kvm->cfg.active_console = CONSOLE_HV;
583 	else
584 		pr_warning("No console!");
585 
586 	if (!kvm->cfg.host_ip)
587 		kvm->cfg.host_ip = DEFAULT_HOST_ADDR;
588 
589 	if (!kvm->cfg.guest_ip)
590 		kvm->cfg.guest_ip = DEFAULT_GUEST_ADDR;
591 
592 	if (!kvm->cfg.guest_mac)
593 		kvm->cfg.guest_mac = DEFAULT_GUEST_MAC;
594 
595 	if (!kvm->cfg.host_mac)
596 		kvm->cfg.host_mac = DEFAULT_HOST_MAC;
597 
598 	if (!kvm->cfg.script)
599 		kvm->cfg.script = DEFAULT_SCRIPT;
600 
601 	if (!kvm->cfg.network)
602                 kvm->cfg.network = DEFAULT_NETWORK;
603 
604 	memset(real_cmdline, 0, sizeof(real_cmdline));
605 	kvm__arch_set_cmdline(real_cmdline, kvm->cfg.vnc || kvm->cfg.sdl || kvm->cfg.gtk);
606 
607 	if (strlen(real_cmdline) > 0)
608 		strcat(real_cmdline, " ");
609 
610 	if (kvm->cfg.kernel_cmdline)
611 		strlcat(real_cmdline, kvm->cfg.kernel_cmdline, sizeof(real_cmdline));
612 
613 	if (!kvm->cfg.guest_name) {
614 		if (kvm->cfg.custom_rootfs) {
615 			kvm->cfg.guest_name = kvm->cfg.custom_rootfs_name;
616 		} else {
617 			sprintf(default_name, "guest-%u", getpid());
618 			kvm->cfg.guest_name = default_name;
619 		}
620 	}
621 
622 	if (!kvm->cfg.using_rootfs && !kvm->cfg.disk_image[0].filename && !kvm->cfg.initrd_filename) {
623 		char tmp[PATH_MAX];
624 
625 		kvm_setup_create_new(kvm->cfg.custom_rootfs_name);
626 		kvm_setup_resolv(kvm->cfg.custom_rootfs_name);
627 
628 		snprintf(tmp, PATH_MAX, "%s%s", kvm__get_dir(), "default");
629 		if (virtio_9p__register(kvm, tmp, "/dev/root") < 0)
630 			die("Unable to initialize virtio 9p");
631 		if (virtio_9p__register(kvm, "/", "hostfs") < 0)
632 			die("Unable to initialize virtio 9p");
633 		kvm->cfg.using_rootfs = kvm->cfg.custom_rootfs = 1;
634 	}
635 
636 	if (kvm->cfg.using_rootfs) {
637 		strcat(real_cmdline, " root=/dev/root rw rootflags=rw,trans=virtio,version=9p2000.L rootfstype=9p");
638 		if (kvm->cfg.custom_rootfs) {
639 			kvm_run_set_sandbox(kvm);
640 
641 			strcat(real_cmdline, " init=/virt/init");
642 
643 			if (!kvm->cfg.no_dhcp)
644 				strcat(real_cmdline, "  ip=dhcp");
645 			if (kvm_setup_guest_init(kvm))
646 				die("Failed to setup init for guest.");
647 		}
648 	} else if (!strstr(real_cmdline, "root=")) {
649 		strlcat(real_cmdline, " root=/dev/vda rw ", sizeof(real_cmdline));
650 	}
651 
652 	kvm->cfg.real_cmdline = real_cmdline;
653 
654 	printf("  # %s run -k %s -m %Lu -c %d --name %s\n", KVM_BINARY_NAME,
655 		kvm->cfg.kernel_filename, kvm->cfg.ram_size / 1024 / 1024, kvm->cfg.nrcpus, kvm->cfg.guest_name);
656 
657 	if (init_list__init(kvm) < 0)
658 		die ("Initialisation failed");
659 
660 	return kvm;
661 }
662 
663 static int kvm_cmd_run_work(struct kvm *kvm)
664 {
665 	int i;
666 	void *ret = NULL;
667 
668 	for (i = 0; i < kvm->nrcpus; i++) {
669 		if (pthread_create(&kvm->cpus[i]->thread, NULL, kvm_cpu_thread, kvm->cpus[i]) != 0)
670 			die("unable to create KVM VCPU thread");
671 	}
672 
673 	/* Only VCPU #0 is going to exit by itself when shutting down */
674 	return pthread_join(kvm->cpus[0]->thread, &ret);
675 }
676 
677 static void kvm_cmd_run_exit(struct kvm *kvm, int guest_ret)
678 {
679 	compat__print_all_messages();
680 
681 	init_list__exit(kvm);
682 
683 	if (guest_ret == 0)
684 		printf("\n  # KVM session ended normally.\n");
685 }
686 
687 int kvm_cmd_run(int argc, const char **argv, const char *prefix)
688 {
689 	int ret = -EFAULT;
690 	struct kvm *kvm;
691 
692 	kvm = kvm_cmd_run_init(argc, argv);
693 	if (IS_ERR(kvm))
694 		return PTR_ERR(kvm);
695 
696 	ret = kvm_cmd_run_work(kvm);
697 	kvm_cmd_run_exit(kvm, ret);
698 
699 	return ret;
700 }
701