NFP is refusing to offload programs whenever the MTU is set to a value larger than the max packet bytes that fits in NFP Cluster Target Memory (CTM). However, a eBPF program doesn't always need to access the whole packet data.
Verifier has always calculated maximum direct packet access (DPA) offset, and kept it in max_pkt_offset inside prog auxiliar information. This patch relax prog rejection based on max_pkt_offset. Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Jiong Wang <[email protected]> --- drivers/net/ethernet/netronome/nfp/bpf/offload.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/netronome/nfp/bpf/offload.c b/drivers/net/ethernet/netronome/nfp/bpf/offload.c index ba8ceed..07bdc1f 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/offload.c +++ b/drivers/net/ethernet/netronome/nfp/bpf/offload.c @@ -489,14 +489,15 @@ nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog, struct netlink_ext_ack *extack) { struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv; - unsigned int max_mtu, max_stack, max_prog_len; + unsigned int fw_mtu, pkt_off, max_stack, max_prog_len; dma_addr_t dma_addr; void *img; int err; - max_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32; - if (max_mtu < nn->dp.netdev->mtu) { - NL_SET_ERR_MSG_MOD(extack, "BPF offload not supported with MTU larger than HW packet split boundary"); + fw_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32; + pkt_off = min(prog->aux->max_pkt_offset, nn->dp.netdev->mtu); + if (fw_mtu < pkt_off) { + NL_SET_ERR_MSG_MOD(extack, "BPF offload not supported with potential packet access beyond HW packet split boundary"); return -EOPNOTSUPP; } -- 2.7.4
