Instead of BUG_ON(in_interrupt()), since that doesn't check for all the newfangled stuff like preempt.
Note that this is valid since the console_sem is essentially used like a real mutex with only two twists: - we allow trylock from hardirq context - across suspend/resume we lock the logical console_lock, but drop the semaphore protecting the locking state.
Now that doesn't guarantee that no one is playing tricks in single-thread atomic contexts at suspend/resume/boot time, but - I couldn't find anything suspicious with some grepping, - might_sleep shouldn't die, - and I think the upside of catching more potential issues is worth the risk of getting a might_sleep backtrace that would have been save (and then dealing with that fallout).
Cc: Dave Airlie airlied@gmail.com Cc: Thomas Gleixner tglx@linutronix.de Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch --- kernel/printk.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/printk.c b/kernel/printk.c index 66a2ea3..ed9af6a 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -1909,7 +1909,8 @@ static int __cpuinit console_cpu_notify(struct notifier_block *self, */ void console_lock(void) { - BUG_ON(in_interrupt()); + might_sleep(); + down(&console_sem); if (console_suspended) return;