Jakub Kicinski wrote: > On Thu, 08 Oct 2020 16:08:57 +0200 Jesper Dangaard Brouer wrote: > > V3: Drop enforcement of MTU in net-core, leave it to drivers > > Sorry for being late to the discussion. > > I absolutely disagree. We had cases in the past where HW would lock up > if it was sent a frame with bad geometry. > > We will not be sprinkling validation checks across the drivers because > some reconfiguration path may occasionally yield a bad packet, or it's > hard to do something right with BPF. This is a driver bug then. As it stands today drivers may get hit with skb with MTU greater than set MTU as best I can tell. Generally I expect drivers use MTU to configure RX buffers not sure how it is going to be used on TX side? Any examples? I just poked around through the driver source to see and seems to confirm its primarily for RX side configuration with some drivers throwing the event down to the firmware for something that I can't see in the code? I'm not suggestiong sprinkling validation checks across the drivers. I'm suggesting if the drivers hang we fix them.
