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
kmsg_dumper_stdout(struct kmsg_dumper * dumper,enum kmsg_dump_reason reason)10 static 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
20 /* only dump kmsg when no console is available */
21 if (!console_trylock())
22 return;
23
24 for_each_console(con) {
25 if(strcmp(con->name, "tty") == 0 &&
26 (con->flags & (CON_ENABLED | CON_CONSDEV)) != 0) {
27 break;
28 }
29 }
30
31 console_unlock();
32
33 if (con)
34 return;
35
36 if (!spin_trylock_irqsave(&lock, flags))
37 return;
38
39 kmsg_dump_rewind(&iter);
40
41 printf("kmsg_dump:\n");
42 while (kmsg_dump_get_line(&iter, true, line, sizeof(line), &len)) {
43 line[len] = '\0';
44 printf("%s", line);
45 }
46
47 spin_unlock_irqrestore(&lock, flags);
48 }
49
50 static struct kmsg_dumper kmsg_dumper = {
51 .dump = kmsg_dumper_stdout
52 };
53
kmsg_dumper_stdout_init(void)54 int __init kmsg_dumper_stdout_init(void)
55 {
56 return kmsg_dump_register(&kmsg_dumper);
57 }
58
59 __uml_postsetup(kmsg_dumper_stdout_init);
60