Taking over the console involves allocating mem with GFP_KERNEL, talking to drm drivers, etc. So this should not be done from an atomic context.
But the console-output trigger deferred console takeover may happen from an atomic context, which leads to "BUG: sleeping function called from invalid context" errors.
This commit fixes these errors by doing the deferred takeover from a workqueue when the notifier runs from an atomic context.
Signed-off-by: Hans de Goede hdegoede@redhat.com --- drivers/video/fbdev/core/fbcon.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-)
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index ef8b2d0b7071..4e5997d53fc4 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -3592,7 +3592,20 @@ static int fbcon_init_device(void) }
#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER +static void fbcon_register_existing_fbs(struct work_struct *work) +{ + int i; + + console_lock(); + + for_each_registered_fb(i) + fbcon_fb_registered(registered_fb[i]); + + console_unlock(); +} + static struct notifier_block fbcon_output_nb; +static DECLARE_WORK(fbcon_deferred_takeover_work, fbcon_register_existing_fbs);
static int fbcon_output_notifier(struct notifier_block *nb, unsigned long action, void *data) @@ -3607,8 +3620,12 @@ static int fbcon_output_notifier(struct notifier_block *nb, deferred_takeover = false; logo_shown = FBCON_LOGO_DONTSHOW;
- for_each_registered_fb(i) - fbcon_fb_registered(registered_fb[i]); + if (in_atomic() || irqs_disabled()) { + schedule_work(&fbcon_deferred_takeover_work); + } else { + for_each_registered_fb(i) + fbcon_fb_registered(registered_fb[i]); + }
return NOTIFY_OK; }