On Fri, 2006-06-02 at 09:53 +0000, Frederik Deweerdt wrote:
> On Fri, Jun 02, 2006 at 11:10:10AM +0800, Zhu Yi wrote:
> > On Thu, 2006-06-01 at 16:42 +0200, Frederik Deweerdt wrote:
> > > This got rid of the oops for me, is it the right fix?
> > 
> > I don't think netlink will contend with hardirqs. Can you test with this
> > fix for ipw2200 driver?
> > 
> It does work, thanks. But doesn't this add a possibility of missing 
> some interrupts?
> 	cpu0				cpu1
>         ====				====
> in isr				in tasklet
> 
> 				ipw_enable_interrupts
> 				|->priv->status |= STATUS_INT_ENABLED;

This is unlikely. cpu0 should not receive ipw2200 interrupt since the
interrupt is disabled until HERE (see below).

> ipw_disable_interrupts
> |->priv->status &= ~STATUS_INT_ENABLED;
> |->ipw_write32(priv, IPW_INTA_MASK_R, ~IPW_INTA_MASK_ALL);
> 
> 				|->ipw_write32(priv, IPW_INTA_MASK_R, IPW_INTA_MASK_ALL);
> 				/* This is possible due to priv->lock no longer being taken
> 				   in isr */

				HERE


Well, this is not 100% if when the card fires two consecutive
interrupts. Though unlikely, it's better to protect early than seeing
some "weird" bugs one day. I proposed attached patch. If you can help to
test, that will be appreciated (I cannot see the lockdep warning on my
box somehow).

Thanks,
-yi