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 X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 798A6C433E0 for ; Thu, 25 Feb 2021 00:48:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2FE3E64EDB for ; Thu, 25 Feb 2021 00:48:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236401AbhBYAsN (ORCPT ); Wed, 24 Feb 2021 19:48:13 -0500 Received: from mail.kernel.org ([198.145.29.99]:44086 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236366AbhBYAsF (ORCPT ); Wed, 24 Feb 2021 19:48:05 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B22DA6146B; Thu, 25 Feb 2021 00:47:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1614214044; bh=v9Cemz6+5QAlytl+WWIeYFPOPcg34dVPzVpn7Ai5Kbw=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=MbLCz8HFy4albGGaAxeg4DicoNj4dZI5iynJgXU/NsF8WsILKvj+eqHB9Vphr5thB a+v8u35WFikt58r/new7tuteQEpeXz0BPZda2yKfwfAXywmHnlGc8GdcXjW/DHn4f8 9S/m2GeerM10HksfNa/H89VAgmt8HzUYiUrjVK13ZRxb+QA6lCQKqbeZPTjwdBDVlb MaVHRzW29g0Q/aD6awdU3cHJniScZwcYcR1Opfy/gYImRqa4Wp+qM3NWbSaCDYrdmA h4+gY6mCiZcqGJrFctn8iIDBaQStqYzHlDaLRoNhnUfadNgwTrmxX83v4Tafma2exe 6ZCL5ZFfEF05A== Date: Wed, 24 Feb 2021 16:47:20 -0800 From: Jakub Kicinski To: Coiby Xu Cc: netdev@vger.kernel.org, kexec@lists.infradead.org, intel-wired-lan@lists.osuosl.org, Jesse Brandeburg , Tony Nguyen , "David S. Miller" , open list Subject: Re: [RFC PATCH 4/4] i40e: don't open i40iw client for kdump Message-ID: <20210224164720.2228c580@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <20210225002101.hvbpq7f6zbvylqy4@Rk> References: <20210222070701.16416-1-coxu@redhat.com> <20210222070701.16416-5-coxu@redhat.com> <20210223122207.08835e0b@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <20210224114141.ziywca4dvn5fs6js@Rk> <20210224084841.50620776@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <20210225002101.hvbpq7f6zbvylqy4@Rk> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 25 Feb 2021 08:21:01 +0800 Coiby Xu wrote: > On Wed, Feb 24, 2021 at 08:48:41AM -0800, Jakub Kicinski wrote: > >On Wed, 24 Feb 2021 19:41:41 +0800 Coiby Xu wrote: > >> I'm not sure if I understand you correctly. Do you mean we shouldn't > >> disable i40iw for kdump? > > > >Forgive my ignorance - are the kdump kernels separate builds? > > AFAIK we don't build a kernel exclusively for kdump. > > >If they are it'd be better to leave the choice of enabling RDMA > >to the user - through appropriate Kconfig options. > > i40iw is usually built as a loadable module. So if we want to leave the > choce of enabling RDMA to the user, we could exclude this driver when > building the initramfs for kdump, for example, dracut provides the > omit_drivers option for this purpose. > > On the other hand, the users expect "crashkernel=auto" to work out of > the box. So i40iw defeats this purpose. > > I'll discuss with my Red Hat team and the Intel team about whether RDMA > is needed for kdump. Thanks for bringing up this issue! Great, talking to experts here at FB it seems that building a cut-down kernel for kdump is easier than chasing all the drivers to react to is_kdump_kernel(). But if you guys need it and Intel is fine with the change I won't complain.