mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-12 13:55:32 +00:00
04a418495e
Add a kmsg_dumper, that dumps the kmsg buffer to stdout, when no console is available. This an enables the printing of early panic() calls triggered in uml_postsetup(). When a panic() call happens so early in the UML kernel no earlyprintk/console is available yet, but with a kmsg_dumper in place the kernel message buffer will be outputted to the user, to give a better hint, of what the failure was. Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Richard Weinberger <richard@nod.at>
43 lines
839 B
C
43 lines
839 B
C
#include <linux/kmsg_dump.h>
|
|
#include <linux/console.h>
|
|
#include <shared/init.h>
|
|
#include <shared/kern.h>
|
|
#include <os.h>
|
|
|
|
static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
|
|
enum kmsg_dump_reason reason)
|
|
{
|
|
static char line[1024];
|
|
|
|
size_t len = 0;
|
|
bool con_available = false;
|
|
|
|
/* only dump kmsg when no console is available */
|
|
if (!console_trylock())
|
|
return;
|
|
|
|
if (console_drivers != NULL)
|
|
con_available = true;
|
|
|
|
console_unlock();
|
|
|
|
if (con_available == true)
|
|
return;
|
|
|
|
printf("kmsg_dump:\n");
|
|
while (kmsg_dump_get_line(dumper, true, line, sizeof(line), &len)) {
|
|
line[len] = '\0';
|
|
printf("%s", line);
|
|
}
|
|
}
|
|
|
|
static struct kmsg_dumper kmsg_dumper = {
|
|
.dump = kmsg_dumper_stdout
|
|
};
|
|
|
|
int __init kmsg_dumper_stdout_init(void)
|
|
{
|
|
return kmsg_dump_register(&kmsg_dumper);
|
|
}
|
|
|
|
__uml_postsetup(kmsg_dumper_stdout_init);
|