From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: Re: [PATCH] net: introduce SO_BPF_EXTENSIONS Date: Fri, 29 Nov 2013 15:13:03 +0100 Message-ID: <5298A0EF.70401@redhat.com> References: <1385639832-3938-1-git-send-email-msekleta@redhat.com> <1385659889.5352.25.camel@edumazet-glaptop2.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Michal Sekletar , netdev@vger.kernel.org, Michael Kerrisk To: Eric Dumazet Return-path: Received: from mx1.redhat.com ([209.132.183.28]:31211 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751448Ab3K2ONN (ORCPT ); Fri, 29 Nov 2013 09:13:13 -0500 In-Reply-To: <1385659889.5352.25.camel@edumazet-glaptop2.roam.corp.google.com> Sender: netdev-owner@vger.kernel.org List-ID: On 11/28/2013 06:31 PM, Eric Dumazet wrote: > On Thu, 2013-11-28 at 12:57 +0100, Michal Sekletar wrote: > >> +enum { >> + BPF_ANC_FLAG_PROTOCOL = (1 << 0), >> + BPF_ANC_FLAG_PKTTYPE = (1 << 1), >> + BPF_ANC_FLAG_IFINDEX = (1 << 2), >> + BPF_ANC_FLAG_NLATTR = (1 << 3), >> + BPF_ANC_FLAG_NLATTR_NEST = (1 << 4), >> + BPF_ANC_FLAG_MARK = (1 << 5), >> + BPF_ANC_FLAG_QUEUE = (1 << 6), >> + BPF_ANC_FLAG_HATYPE = (1 << 7), >> + BPF_ANC_FLAG_RXHASH = (1 << 8), >> + BPF_ANC_FLAG_CPU = (1 << 9), >> + BPF_ANC_FLAG_ALU_XOR_X = (1 << 10), >> + BPF_ANC_FLAG_SECCOMP_LD_W = (1 << 11), >> + BPF_ANC_FLAG_VLAN_TAG = (1 << 12), >> + BPF_ANC_FLAG_VLAN_TAG_PRESENT = (1 << 13), >> + BPF_ANC_FLAG_PAY_OFFSET = (1 << 14), >> +}; >> + > > Why spending 15 bits (out of 32), for all these extensions ? > > It seems a single one should be enough. > > I do not think we will ever remove one of these extension. Agreed, this will just cripple of us adding other extensions in terms of uapi. I assume there won't be so much more extensions, but it's of course hard to predict the future. ;-)