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=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 9514BC433DF for ; Wed, 29 Jul 2020 01:15:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26CAD207E8 for ; Wed, 29 Jul 2020 01:15:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ellerman.id.au header.i=@ellerman.id.au header.b="UxEKgHV0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730041AbgG2BPU (ORCPT ); Tue, 28 Jul 2020 21:15:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50962 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726004AbgG2BPU (ORCPT ); Tue, 28 Jul 2020 21:15:20 -0400 Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15074C061794 for ; Tue, 28 Jul 2020 18:15:20 -0700 (PDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4BGbFJ0Qhjz9sRW; Wed, 29 Jul 2020 11:15:16 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1595985317; bh=uLD3L3DOKgJ2d1NC32eZyYYdag6TLa6nReuwfKtIbCg=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=UxEKgHV0KiOjp3qRusBz2S3sjmtAiTE1oCvCgnfRuEuSn1kkp+Jx0+MEF+ozPCAZC x8bgKeVUNY+wXri/8XnjJj7suHZNu/l639huAXpHph568BQdZAU2U94bzjyWldttvm mVl1zrsh+yNPRMb5kinHvGdaqjFIECn5/kQf9b6EOCxouOzKdxofVz1ytU0QacXDkv J7cRYJDeEhRrJ83DCGVu7+4MCdj2lmStKpttXXR0fg6s6WPeMCZpyOgs/D4+6ZfFHT u7BUtR8ieCbqkSmiRkuMWiwgLNA+cgTtRX7AIZMAqS3uteJB1AJUmC+1v350NVhRjn gB+xizwWf4WaQ== From: Michael Ellerman To: Hari Bathini , Andrew Morton Cc: Pingfan Liu , Kexec-ml , Mimi Zohar , Nayna Jain , Petr Tesarik , Mahesh J Salgaonkar , Sourabh Jain , lkml , linuxppc-dev , Eric Biederman , Thiago Jung Bauermann , Dave Young , Vivek Goyal Subject: Re: [RESEND PATCH v5 07/11] ppc64/kexec_file: enable early kernel's OPAL calls In-Reply-To: <23baef6a-6ddc-572a-82c5-21a7fa441485@linux.ibm.com> References: <159579157320.5790.6748078824637688685.stgit@hbathini> <159579233676.5790.10701756666641782647.stgit@hbathini> <87365b7nx4.fsf@mpe.ellerman.id.au> <23baef6a-6ddc-572a-82c5-21a7fa441485@linux.ibm.com> Date: Wed, 29 Jul 2020 11:15:12 +1000 Message-ID: <87v9i75dgf.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hari Bathini writes: > On 28/07/20 7:16 pm, Michael Ellerman wrote: >> Hari Bathini writes: >>> Kernel built with CONFIG_PPC_EARLY_DEBUG_OPAL enabled expects r8 & r9 >>> to be filled with OPAL base & entry addresses respectively. Setting >>> these registers allows the kernel to perform OPAL calls before the >>> device tree is parsed. >> >> I'm not convinced we want to do this. >> >> If we do it becomes part of the kexec ABI and we have to honour it into >> the future. >> >> And in practice there are no non-development kernels built with OPAL early >> debugging enabled, so it's not clear it actually helps anyone other than >> developers. >> > > Hmmm.. kexec-tools does it since commit d58ad564852c ("kexec/ppc64 > Enable early kernel's OPAL calls") for kexec_load syscall. So, we would > be breaking kexec ABI either way, I guess. Ugh, OK. > Let me put this patch at the end of the series in the respin to let you > decide whether to have it or not.. Thanks. cheers 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=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,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 8179CC433E0 for ; Wed, 29 Jul 2020 01:17:12 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B0E7D207E8 for ; Wed, 29 Jul 2020 01:17:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=ellerman.id.au header.i=@ellerman.id.au header.b="UxEKgHV0" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B0E7D207E8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BGbHT3FzmzDr5V for ; Wed, 29 Jul 2020 11:17:09 +1000 (AEST) Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4BGbFK4810zDqxD for ; Wed, 29 Jul 2020 11:15:17 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=ellerman.id.au header.i=@ellerman.id.au header.a=rsa-sha256 header.s=201909 header.b=UxEKgHV0; dkim-atps=neutral Received: by ozlabs.org (Postfix) id 4BGbFK1TbMz9sSy; Wed, 29 Jul 2020 11:15:17 +1000 (AEST) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4BGbFJ0Qhjz9sRW; Wed, 29 Jul 2020 11:15:16 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1595985317; bh=uLD3L3DOKgJ2d1NC32eZyYYdag6TLa6nReuwfKtIbCg=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=UxEKgHV0KiOjp3qRusBz2S3sjmtAiTE1oCvCgnfRuEuSn1kkp+Jx0+MEF+ozPCAZC x8bgKeVUNY+wXri/8XnjJj7suHZNu/l639huAXpHph568BQdZAU2U94bzjyWldttvm mVl1zrsh+yNPRMb5kinHvGdaqjFIECn5/kQf9b6EOCxouOzKdxofVz1ytU0QacXDkv J7cRYJDeEhRrJ83DCGVu7+4MCdj2lmStKpttXXR0fg6s6WPeMCZpyOgs/D4+6ZfFHT u7BUtR8ieCbqkSmiRkuMWiwgLNA+cgTtRX7AIZMAqS3uteJB1AJUmC+1v350NVhRjn gB+xizwWf4WaQ== From: Michael Ellerman To: Hari Bathini , Andrew Morton Subject: Re: [RESEND PATCH v5 07/11] ppc64/kexec_file: enable early kernel's OPAL calls In-Reply-To: <23baef6a-6ddc-572a-82c5-21a7fa441485@linux.ibm.com> References: <159579157320.5790.6748078824637688685.stgit@hbathini> <159579233676.5790.10701756666641782647.stgit@hbathini> <87365b7nx4.fsf@mpe.ellerman.id.au> <23baef6a-6ddc-572a-82c5-21a7fa441485@linux.ibm.com> Date: Wed, 29 Jul 2020 11:15:12 +1000 Message-ID: <87v9i75dgf.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pingfan Liu , Kexec-ml , Nayna Jain , Petr Tesarik , Mahesh J Salgaonkar , Mimi Zohar , lkml , linuxppc-dev , Sourabh Jain , Vivek Goyal , Dave Young , Thiago Jung Bauermann , Eric Biederman Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hari Bathini writes: > On 28/07/20 7:16 pm, Michael Ellerman wrote: >> Hari Bathini writes: >>> Kernel built with CONFIG_PPC_EARLY_DEBUG_OPAL enabled expects r8 & r9 >>> to be filled with OPAL base & entry addresses respectively. Setting >>> these registers allows the kernel to perform OPAL calls before the >>> device tree is parsed. >> >> I'm not convinced we want to do this. >> >> If we do it becomes part of the kexec ABI and we have to honour it into >> the future. >> >> And in practice there are no non-development kernels built with OPAL early >> debugging enabled, so it's not clear it actually helps anyone other than >> developers. >> > > Hmmm.. kexec-tools does it since commit d58ad564852c ("kexec/ppc64 > Enable early kernel's OPAL calls") for kexec_load syscall. So, we would > be breaking kexec ABI either way, I guess. Ugh, OK. > Let me put this patch at the end of the series in the respin to let you > decide whether to have it or not.. Thanks. cheers From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ozlabs.org ([2401:3900:2:1::2]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1k0agj-00073q-Jq for kexec@lists.infradead.org; Wed, 29 Jul 2020 01:15:22 +0000 From: Michael Ellerman Subject: Re: [RESEND PATCH v5 07/11] ppc64/kexec_file: enable early kernel's OPAL calls In-Reply-To: <23baef6a-6ddc-572a-82c5-21a7fa441485@linux.ibm.com> References: <159579157320.5790.6748078824637688685.stgit@hbathini> <159579233676.5790.10701756666641782647.stgit@hbathini> <87365b7nx4.fsf@mpe.ellerman.id.au> <23baef6a-6ddc-572a-82c5-21a7fa441485@linux.ibm.com> Date: Wed, 29 Jul 2020 11:15:12 +1000 Message-ID: <87v9i75dgf.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Hari Bathini , Andrew Morton Cc: Pingfan Liu , Kexec-ml , Nayna Jain , Petr Tesarik , Mahesh J Salgaonkar , Mimi Zohar , lkml , linuxppc-dev , Sourabh Jain , Vivek Goyal , Dave Young , Thiago Jung Bauermann , Eric Biederman Hari Bathini writes: > On 28/07/20 7:16 pm, Michael Ellerman wrote: >> Hari Bathini writes: >>> Kernel built with CONFIG_PPC_EARLY_DEBUG_OPAL enabled expects r8 & r9 >>> to be filled with OPAL base & entry addresses respectively. Setting >>> these registers allows the kernel to perform OPAL calls before the >>> device tree is parsed. >> >> I'm not convinced we want to do this. >> >> If we do it becomes part of the kexec ABI and we have to honour it into >> the future. >> >> And in practice there are no non-development kernels built with OPAL early >> debugging enabled, so it's not clear it actually helps anyone other than >> developers. >> > > Hmmm.. kexec-tools does it since commit d58ad564852c ("kexec/ppc64 > Enable early kernel's OPAL calls") for kexec_load syscall. So, we would > be breaking kexec ABI either way, I guess. Ugh, OK. > Let me put this patch at the end of the series in the respin to let you > decide whether to have it or not.. Thanks. cheers _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec