At Tue, 1 Apr 2014 13:37:00 +0200, Jiri Slaby wrote: > > The 8250 driver now reports many of these: > serial8250: too much work for irq4 > These messages turned out to be common these days with a use of > virtualization. I tried to increase the limit of processed characters > in commit e7328ae1848966181a7ac47e8ae6cddbd2cf55f3 (serial: 8250, > increase PASS_LIMIT) in 2011. It was raised from 256 to 512, but it is > still not enough, apparently.
Actually, it looks like a side-effect of the reduction of tasklet. In the earlier code, tty_wakeup() was called via tasklet, and this made the loop in the interrupt handler finishing once. Now it's called directly, thus the irq handler may pick up more than before. > So disable the warning unless somebody turns on DEBUG (or > DYNAMIC_DEBUG _and_ the message). > > Signed-off-by: Jiri Slaby <[email protected]> > Reported-by: Martin Pluskal <[email protected]> > Reported-by: Takashi Iwai <[email protected]> > References: https://bugzilla.novell.com/show_bug.cgi?id=868394 In case it's still worth: Tested-by: Takashi Iwai <[email protected]> thanks, Takashi > --- > drivers/tty/serial/8250/8250_core.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/tty/serial/8250/8250_core.c > b/drivers/tty/serial/8250/8250_core.c > index 81f909c2101f..139ab1997e06 100644 > --- a/drivers/tty/serial/8250/8250_core.c > +++ b/drivers/tty/serial/8250/8250_core.c > @@ -1601,8 +1601,7 @@ static irqreturn_t serial8250_interrupt(int irq, void > *dev_id) > l = l->next; > > if (l == i->head && pass_counter++ > PASS_LIMIT) { > - /* If we hit this, we're dead. */ > - printk_ratelimited(KERN_ERR > + pr_debug_ratelimited( > "serial8250: too much work for irq%d\n", irq); > break; > } > -- > 1.9.1 > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
