serial: kgdb_nmi: Improve console integration with KDB I/O
kgdb_nmi_tty_enabled is used for two unrelated purposes, namely to
suppress normal TTY input handling and to suppress console output
(although it has no effect at all on TTY output). A much better way to
handle muting the console is to not have to mute it in the first place!
That's what this patch does.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/kgdb_nmi.c b/drivers/tty/serial/kgdb_nmi.c
index 20d21d0..cfadf29 100644
--- a/drivers/tty/serial/kgdb_nmi.c
+++ b/drivers/tty/serial/kgdb_nmi.c
@@ -44,13 +44,22 @@
static bool kgdb_nmi_tty_enabled;
+static int kgdb_nmi_console_setup(struct console *co, char *options)
+{
+ /* The NMI console uses the dbg_io_ops to issue console messages. To
+ * avoid duplicate messages during kdb sessions we must inform kdb's
+ * I/O utilities that messages sent to the console will automatically
+ * be displayed on the dbg_io.
+ */
+ dbg_io_ops->is_console = true;
+
+ return 0;
+}
+
static void kgdb_nmi_console_write(struct console *co, const char *s, uint c)
{
int i;
- if (!kgdb_nmi_tty_enabled || atomic_read(&kgdb_active) >= 0)
- return;
-
for (i = 0; i < c; i++)
dbg_io_ops->write_char(s[i]);
}
@@ -65,6 +74,7 @@
static struct console kgdb_nmi_console = {
.name = "ttyNMI",
+ .setup = kgdb_nmi_console_setup,
.write = kgdb_nmi_console_write,
.device = kgdb_nmi_console_device,
.flags = CON_PRINTBUFFER | CON_ANYTIME | CON_ENABLED,