Re: [PATCH bpf-next v3 07/11] bpf: make tun compatible w/ bpf_xdp_adjust_tail

2018-04-18 Thread Michael S. Tsirkin
On Tue, Apr 17, 2018 at 09:42:19PM -0700, Nikita V. Shirokov wrote: > w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as > well (only "decrease" of pointer's location is going to be supported). > changing of this pointer will change packet's size. > for tun driver we need to

[PATCH bpf-next v3 07/11] bpf: make tun compatible w/ bpf_xdp_adjust_tail

2018-04-18 Thread Nikita V. Shirokov
w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as well (only "decrease" of pointer's location is going to be supported). changing of this pointer will change packet's size. for tun driver we need to adjust XDP_PASS handling by recalculating length of the packet if it was