1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/kmsg_dump.h>
 
 3#include <linux/console.h>
 
 4#include <shared/init.h>
 5#include <shared/kern.h>
 6#include <os.h>
 7
 8static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
 9				enum kmsg_dump_reason reason)
10{
 
 
11	static char line[1024];
12
 
13	size_t len = 0;
14	bool con_available = false;
15
16	/* only dump kmsg when no console is available */
17	if (!console_trylock())
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
18		return;
19
20	if (console_drivers != NULL)
21		con_available = true;
22
23	console_unlock();
24
25	if (con_available == true)
26		return;
27
 
 
28	printf("kmsg_dump:\n");
29	while (kmsg_dump_get_line(dumper, true, line, sizeof(line), &len)) {
30		line[len] = '\0';
31		printf("%s", line);
32	}
 
 
33}
34
35static struct kmsg_dumper kmsg_dumper = {
36	.dump = kmsg_dumper_stdout
37};
38
39int __init kmsg_dumper_stdout_init(void)
40{
41	return kmsg_dump_register(&kmsg_dumper);
42}
43
44__uml_postsetup(kmsg_dumper_stdout_init);

 1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/kmsg_dump.h>
 3#include <linux/spinlock.h>
 4#include <linux/console.h>
 5#include <linux/string.h>
 6#include <shared/init.h>
 7#include <shared/kern.h>
 8#include <os.h>
 9
10static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
11				enum kmsg_dump_reason reason)
12{
13	static struct kmsg_dump_iter iter;
14	static DEFINE_SPINLOCK(lock);
15	static char line[1024];
16	struct console *con;
17	unsigned long flags;
18	size_t len = 0;
19	int cookie;
20
21	/*
22	 * If no consoles are available to output crash information, dump
23	 * the kmsg buffer to stdout.
24	 */
25
26	cookie = console_srcu_read_lock();
27	for_each_console_srcu(con) {
28		/*
29		 * The ttynull console and disabled consoles are ignored
30		 * since they cannot output. All other consoles are
31		 * expected to output the crash information.
32		 */
33		if (strcmp(con->name, "ttynull") != 0 &&
34		    (console_srcu_read_flags(con) & CON_ENABLED)) {
35			break;
36		}
37	}
38	console_srcu_read_unlock(cookie);
39	if (con)
40		return;
41
42	if (!spin_trylock_irqsave(&lock, flags))
 
 
 
 
 
43		return;
44
45	kmsg_dump_rewind(&iter);
46
47	printf("kmsg_dump:\n");
48	while (kmsg_dump_get_line(&iter, true, line, sizeof(line), &len)) {
49		line[len] = '\0';
50		printf("%s", line);
51	}
52
53	spin_unlock_irqrestore(&lock, flags);
54}
55
56static struct kmsg_dumper kmsg_dumper = {
57	.dump = kmsg_dumper_stdout
58};
59
60int __init kmsg_dumper_stdout_init(void)
61{
62	return kmsg_dump_register(&kmsg_dumper);
63}
64
65__uml_postsetup(kmsg_dumper_stdout_init);