From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23154C32771 for ; Mon, 26 Sep 2022 15:53:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233732AbiIZPxa (ORCPT ); Mon, 26 Sep 2022 11:53:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234536AbiIZPww (ORCPT ); Mon, 26 Sep 2022 11:52:52 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6E0A891D0D; Mon, 26 Sep 2022 07:40:29 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 0628460E2C; Mon, 26 Sep 2022 14:40:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A5215C433B5; Mon, 26 Sep 2022 14:40:23 +0000 (UTC) Date: Mon, 26 Sep 2022 15:40:20 +0100 From: Catalin Marinas To: Daniel Borkmann Cc: Xu Kuohai , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, Mark Rutland , Florent Revest , Will Deacon , Jean-Philippe Brucker , Steven Rostedt , Ingo Molnar , Oleg Nesterov , Alexei Starovoitov , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Zi Shen Lim , Pasha Tatashin , Ard Biesheuvel , Marc Zyngier , Guo Ren , Masami Hiramatsu Subject: Re: [PATCH bpf-next v2 0/4] Add ftrace direct call for arm64 Message-ID: References: <20220913162732.163631-1-xukuohai@huaweicloud.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 22, 2022 at 08:01:16PM +0200, Daniel Borkmann wrote: > On 9/13/22 6:27 PM, Xu Kuohai wrote: > > This series adds ftrace direct call for arm64, which is required to attach > > bpf trampoline to fentry. > > > > Although there is no agreement on how to support ftrace direct call on arm64, > > no patch has been posted except the one I posted in [1], so this series > > continues the work of [1] with the addition of long jump support. Now ftrace > > direct call works regardless of the distance between the callsite and custom > > trampoline. > > > > [1] https://lore.kernel.org/bpf/20220518131638.3401509-2-xukuohai@huawei.com/ > > > > v2: > > - Fix compile and runtime errors caused by ftrace_rec_arch_init > > > > v1: https://lore.kernel.org/bpf/20220913063146.74750-1-xukuohai@huaweicloud.com/ > > > > Xu Kuohai (4): > > ftrace: Allow users to disable ftrace direct call > > arm64: ftrace: Support long jump for ftrace direct call > > arm64: ftrace: Add ftrace direct call support > > ftrace: Fix dead loop caused by direct call in ftrace selftest > > Given there's just a tiny fraction touching BPF JIT and most are around core arm64, > it probably makes sense that this series goes via Catalin/Will through arm64 tree > instead of bpf-next if it looks good to them. Catalin/Will, thoughts (Ack + bpf-next > could work too, but I'd presume this just results in merge conflicts)? I think it makes sense for the series to go via the arm64 tree but I'd like Mark to have a look at the ftrace changes first. Thanks. -- Catalin