On Tue, 27 Nov 2007 19:52:24 +0100
Robert Olsson [off-list ref] wrote:

Hello!

I've discovered a bug while testing the new multiQ NAPI code. In hi-load 
situations when we take down an interface we get a kernel panic. The
oops is below.

From what I see this happens when driver does napi_disable() and clears
NAPI_STATE_SCHED. In net_rx_action there is a check for work == weight 
a sort indirect test but that's now not enough to cover the load situation. 
where we have NAPI_STATE_SCHED cleared by e1000_down in my case and still 
full quota. Latest git but I'll guess the is the same in all later kernels.
There might be different solutions... one variant is below:

It is considered a driver bug in 2.6.24 to call netif_rx_complete (clear NAPI_STATE_SCHED)
and do a full quota. That bug already had to be fixed in other drivers,
look like e1000 has same problem.


-- 
Stephen Hemminger [off-list ref]