On (09/05/19 12:03), Qian Cai wrote:
> > ---
> > diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
> > index cd51aa7d08a9..89cb47882254 100644
> > --- a/kernel/printk/printk.c
> > +++ b/kernel/printk/printk.c
> > @@ -2027,8 +2027,11 @@ asmlinkage int vprintk_emit(int facility, int level,
> > pending_output = (curr_log_seq != log_next_seq);
> > logbuf_unlock_irqrestore(flags);
> >
> > + if (!pending_output)
> > + return printed_len;
> > +
> > /* If called from the scheduler, we can not call up(). */
> > - if (!in_sched && pending_output) {
> > + if (!in_sched) {
> > /*
> > * Disable preemption to avoid being preempted while holding
> > * console_sem which would prevent anyone from printing to
> > @@ -2043,10 +2046,11 @@ asmlinkage int vprintk_emit(int facility, int level,
> > if (console_trylock_spinning())
> > console_unlock();
> > preempt_enable();
> > - }
> >
> > - if (pending_output)
> > + wake_up_interruptible(&log_wait);
> > + } else {
> > wake_up_klogd();
> > + }
> > return printed_len;
> > }
> > EXPORT_SYMBOL(vprintk_emit);
> > ---
Qian Cai, any chance you can test that patch?
-ss
