[PATCH 21/25] kgdboc,kdb: Allow kdb to work on a non open console port

From: Jason Wessel
Date: Tue May 18 2010 - 21:44:56 EST


If kdb is open on a serial port that is not actually a console make
sure to call the poll routines to emit and receive characters.

Signed-off-by: Jason Wessel <jason.wessel@xxxxxxxxxxxxx>
Acked-by: Martin Hicks <mort@xxxxxxx>
---
drivers/serial/kgdboc.c | 14 ++++++++++++++
include/linux/kgdb.h | 3 +++
kernel/debug/kdb/kdb_io.c | 16 ++++++++++++++++
3 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index ecef6e1..b765ab4 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -16,6 +16,7 @@
#include <linux/kgdb.h>
#include <linux/kdb.h>
#include <linux/tty.h>
+#include <linux/console.h>

#define MAX_CONFIG_LEN 40

@@ -93,12 +94,14 @@ static int configure_kgdboc(void)
int tty_line = 0;
int err;
char *cptr = config;
+ struct console *cons;

err = kgdboc_option_setup(config);
if (err || !strlen(config) || isspace(config[0]))
goto noconfig;

err = -ENODEV;
+ kgdboc_io_ops.is_console = 0;
kgdb_tty_driver = NULL;

if (kgdboc_register_kbd(&cptr))
@@ -108,6 +111,17 @@ static int configure_kgdboc(void)
if (!p)
goto noconfig;

+ cons = console_drivers;
+ while (cons) {
+ int idx;
+ if (cons->device && cons->device(cons, &idx) == p &&
+ idx == tty_line) {
+ kgdboc_io_ops.is_console = 1;
+ break;
+ }
+ cons = cons->next;
+ }
+
kgdb_tty_driver = p;
kgdb_tty_line = tty_line;

diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index ee007ea..6c784ab 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -247,6 +247,8 @@ struct kgdb_arch {
* the I/O driver.
* @post_exception: Pointer to a function that will do any cleanup work
* for the I/O driver.
+ * @is_console: 1 if the end device is a console 0 if the I/O device is
+ * not a console
*/
struct kgdb_io {
const char *name;
@@ -256,6 +258,7 @@ struct kgdb_io {
int (*init) (void);
void (*pre_exception) (void);
void (*post_exception) (void);
+ int is_console;
};

extern struct kgdb_arch arch_kgdb_ops;
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
index 8339b29..58be7e9 100644
--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -673,6 +673,14 @@ kdb_printit:
if (!dbg_kdb_mode && kgdb_connected) {
gdbstub_msg_write(kdb_buffer, retlen);
} else {
+ if (!dbg_io_ops->is_console) {
+ len = strlen(kdb_buffer);
+ cp = kdb_buffer;
+ while (len--) {
+ dbg_io_ops->write_char(*cp);
+ cp++;
+ }
+ }
while (c) {
c->write(c, kdb_buffer, retlen);
touch_nmi_watchdog();
@@ -719,6 +727,14 @@ kdb_printit:
kdb_input_flush();
c = console_drivers;

+ if (!dbg_io_ops->is_console) {
+ len = strlen(moreprompt);
+ cp = moreprompt;
+ while (len--) {
+ dbg_io_ops->write_char(*cp);
+ cp++;
+ }
+ }
while (c) {
c->write(c, moreprompt, strlen(moreprompt));
touch_nmi_watchdog();
--
1.6.3.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/