From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [RFC PATCH v2 tip 0/7] 64-bit BPF insn set and tracing filters Date: Thu, 13 Feb 2014 14:32:25 -0800 Message-ID: <52FD47F9.2090907@zytor.com> References: <1391649046-4383-1-git-send-email-ast@plumgrid.com> <52F3670D.5090608@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Ingo Molnar , "David S. Miller" , Steven Rostedt , Peter Zijlstra , Thomas Gleixner , Masami Hiramatsu , Tom Zanussi , Jovi Zhangwei , Eric Dumazet , Linus Torvalds , Andrew Morton , Frederic Weisbecker , Arnaldo Carvalho de Melo , Pekka Enberg , Arjan van de Ven , Christoph Hellwig , linux-kernel@vger.kernel.org, netdev@vger.kernel.org To: Alexei Starovoitov , Daniel Borkmann Return-path: Received: from terminus.zytor.com ([198.137.202.10]:45115 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751795AbaBMWd3 (ORCPT ); Thu, 13 Feb 2014 17:33:29 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 02/06/2014 05:20 PM, Alexei Starovoitov wrote: > > I believe that old BPF outlived itself and BPF64 should > replace it in all current use cases plus a lot more. > It just cannot happen at once. > BPF64 can come in. bpf32->bpf64 converter functioning. > JIT from bpf64->aarch64 and may be sparc64 needs to be in place. > Then old bpf can fade away. > I don't think that is doable any time soon. Right now pretty much all mobile devices, for example, are 32 bits and they really want to use syscall filtering for security. Performance matters greatly there. As such, 32-bit JIT support is going to be very important for a long time to come. -hpa