Subject: Re: bugreport: The r8169.c driver is calling netif_receive_skb from hardirq and with interrupts off

From: Stephen Hemminger <[email-masked]>
Date: Mon, 14 Apr 2008 11:31:51 -0700

On Mon, 14 Apr 2008 11:24:04 -0700
Arjan van de Ven <[email-masked]> wrote:

> Stephen Hemminger wrote:
> > On Mon, 14 Apr 2008 11:01:16 -0700
> > Arjan van de Ven <[email-masked]> wrote:
> > 
> >> The r8169.c driver is calling netif_receive_skb from hardirq and with interrupts off,
> >> which seems to be invalid (the comments of netif_receive_skb) certainly say so.
> >>
> >> The calltrace is like this:
> >>
> >> packet_rcv
> >> netif_receive_skb
> >> rtl8168_rx_interrupt
> >> rtl8168_interrupt
> >> handle_IRQ_event
> >> handle_fasteoi_irq
> >> do_IRQ
> >>
> >>
> >> Which triggers a warning in packet_rcv() since that does a local_bh_enable(),
> >> which gives a WARN_ON if irqs are disabled (rightfully so it seems).
> >>
> >> The code looks is in rtl8169_rx_interrupt() line 2832 and looks like
> >>
> >>                          if (rtl8169_rx_vlan_skb(tp, desc, skb) < 0)
> >>                                  rtl8169_rx_skb(skb);
> >>
> >> with
> >> #define rtl8169_rx_skb                  netif_receive_skb
> >> higher up in the file.
> >>
> >> This is the 46th highest ranking warnon/oops report for 2.6.25-rc
> >>
> > 
> > rtl8169_rx_skb is defined as netif_receive_skb only if NAPI is enabled.
> > But the backtrace has CONFIG_R8169_NAPI disabled.
> 
> what makes you think this config option is disabled ?
> (just curious)

The receive path for NAPI would be:
	netif_receive_skb
	rtl8169_rx_interrupt
	rtl8169_napi
  
*** But we are both wrong ***
This is not the mainline r8169 driver but more likely the out of tree 
vendor 8168 driver. There is no rtl8168_rx_interrupt in mainline.