dummycon: Sprinkle locking checks

As part of trying to understand the locking (or lack thereof) in the
fbcon/vt/fbdev maze, annotate everything.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-2-daniel.vetter@ffwll.ch

diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index ff886e99104b8aa07e2ee8cbeac077ff6f9375e1..2a0d0bda7faa50d58666ae1aff76a44cf1abbff1 100644 (file)
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -34,6 +34,8 @@ static bool dummycon_putc_called;
 
 void dummycon_register_output_notifier(struct notifier_block *nb)
 {
+       WARN_CONSOLE_UNLOCKED();
+
        raw_notifier_chain_register(&dummycon_output_nh, nb);
 
        if (dummycon_putc_called)
@@ -42,11 +44,15 @@ void dummycon_register_output_notifier(struct notifier_block *nb)
 
 void dummycon_unregister_output_notifier(struct notifier_block *nb)
 {
+       WARN_CONSOLE_UNLOCKED();
+
        raw_notifier_chain_unregister(&dummycon_output_nh, nb);
 }
 
 static void dummycon_putc(struct vc_data *vc, int c, int ypos, int xpos)
 {
+       WARN_CONSOLE_UNLOCKED();
+
        dummycon_putc_called = true;
        raw_notifier_call_chain(&dummycon_output_nh, 0, NULL);
 }