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=-7.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 C5DA9C433FF for ; Mon, 5 Aug 2019 11:17:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9D28F20B1F for ; Mon, 5 Aug 2019 11:17:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565003828; bh=JCiN2ISR81s+2Lx+2tbYurR9+DzYblAfJLh6BdGkxrY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=n/eGKzKlRJ0lEebL4GWEFBCkXxRWMq/S/n0Nv4l0/qoZ81Orh/4i2UQUDpWwfXeD2 HJLtOvWvdHS2Abw/tr9tm5Bte42Iw/dsrmAZWmCzBe7HAv+fc8MggXXQ8lF14U15j1 D7FUgbQosvnN542hVKsOEW3c0zjISx94tSf1xNwA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728446AbfHELRG (ORCPT ); Mon, 5 Aug 2019 07:17:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:41982 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727158AbfHELRG (ORCPT ); Mon, 5 Aug 2019 07:17:06 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 94A3620856; Mon, 5 Aug 2019 11:17:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565003825; bh=JCiN2ISR81s+2Lx+2tbYurR9+DzYblAfJLh6BdGkxrY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=UGNAi4134dElHNtXnff3/vxvYhB9pmlQfEHL460cRQmeChXMUX01Xa6fKwMNcymHM 5w1ncMys94VH6IBbL9L91uAZoIyjS1UFmoJQzpHP8q9jbvZYMjUjQ1srFeB7PMCEiQ xNoh6h815xI/PVEljHzHiIbAzigwaQR2uVgCy0go= Date: Mon, 5 Aug 2019 13:17:02 +0200 From: Greg Kroah-Hartman To: Alexey Brodkin Cc: linux-stable , "linux-kernel@vger.kernel.org" , Corentin Labbe , "khilman@baylibre.com" , "linux-snps-arc@lists.infradead.org" , Eugeniy Paltsev , Vineet Gupta Subject: Re: [PATCH v2 2/2] ARC: enable uboot support unconditionally Message-ID: <20190805111702.GA8189@kroah.com> References: <20190214150745.18773-1-Eugeniy.Paltsev@synopsys.com> <20190214150745.18773-3-Eugeniy.Paltsev@synopsys.com> <20190802074053.GE26174@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 02, 2019 at 04:25:39PM +0000, Alexey Brodkin wrote: > Hi Greg, > > > > May we have this one back-ported to linux-4.19.y? > > > > > > It was initially applied to Linus' tree during 5.0 development > > > cycle [1] but was never back-ported. > > > > > > Now w/o that patch in KernelCI we see boot failure on ARC HSDK > > > board [2] as opposed to normally working later kernel versions. > > > > > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=493a2f812446e92bcb1e69a77381b4d39808d730 > > > [2] https://storage.kernelci.org/stable/linux-4.19.y/v4.19.59/arc/hsdk_defconfig/gcc-8/lab-baylibre/boot-hsdk.txt > > > > > > Below is that same patch but rebased on linux-4.19 as in its pristine > > > form it won't apply due to offset of one of hunks. > > > > Why is this patch ok for stable kernel trees? Are you not removing > > existing support in 4.19 for a feature that people might be using there? > > What bug is this fixing that requires this removal? > > This patch removes a Kconfig option in a trade for properly working > detection of arguments passed from U-Boot. > > Back in the day [3] we had to add that option to get kernel reliably working > in use-cases w/o U-Boot (those were typically loading kernel image via JTAG). > But with a couple of fixes applied to linux-4.19.y already we no longer need > that explicit toggle as we may rely on data passed via dedicated registers > and thus automatically know if there was U-Boot which passed some info to > the kernel or there was no U-Boot and we don't need to mess with garbage in > those registers. > > Main reason is to make vanilla 4.19.y kernels usable on HSDK board in KernelCI > environment. Now they don't boot, see [2] as in HSDK's defconfig ARC_UBOOT_SUPPORT > is not set. So we have 2 solutions: > > 1. Add ARC_UBOOT_SUPPORT to arch/arc/configs/hsdk_defconfig > But we cannot do it for vanilla kernel because we simply cannot even submit that > change to the Linus' tree as that Kconfig option was removed. > Which means we cannot back-port it, right :) > > 2. Back-port proposed patch which already exists in the Linus'tree and thus is > perfectly back-portable. > > Makes sense? Ok, it's your arch, you get to deal with the angry users if you have any :) now queued up. greg k-h