On Tue, Apr 20, 2021 at 01:01:44PM -0700, Eric Dumazet wrote: > From: Eric Dumazet <[email protected]> > > build_skb() is supposed to be followed by > skb_reserve(skb, NET_IP_ALIGN), so that IP headers are word-aligned. > (Best practice is to reserve NET_IP_ALIGN+NET_SKB_PAD, but the NET_SKB_PAD > part is only a performance optimization if tunnel encaps are added.) > > Unfortunately virtio_net has not provisioned this reserve. > We can only use build_skb() for arches where NET_IP_ALIGN == 0 > > We might refine this later, with enough testing. > > Fixes: fb32856b16ad ("virtio-net: page_to_skb() use build_skb when there's > sufficient tailroom") > Signed-off-by: Eric Dumazet <[email protected]> > Reported-by: Guenter Roeck <[email protected]> > Cc: Xuan Zhuo <[email protected]> > Cc: Jason Wang <[email protected]> > Cc: "Michael S. Tsirkin" <[email protected]> > Cc: [email protected]
Tested-by: Guenter Roeck <[email protected]> on alpha, sh4 (little endian). Thanks! Guenter
