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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 ACFBFC433DF for ; Mon, 18 May 2020 12:24:11 +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 2BD372067D for ; Mon, 18 May 2020 12:24:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2BD372067D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org 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 49QdVH4nPrzDqZF for ; Mon, 18 May 2020 22:24:07 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=permerror (SPF Permanent Error: Unknown mechanism found: ip:192.40.192.88/32) smtp.mailfrom=kernel.crashing.org (client-ip=63.228.1.57; helo=gate.crashing.org; envelope-from=segher@kernel.crashing.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by lists.ozlabs.org (Postfix) with ESMTP id 49QdNv3Z8nzDqfk for ; Mon, 18 May 2020 22:19:27 +1000 (AEST) Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id 04ICJHhM015578; Mon, 18 May 2020 07:19:18 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id 04ICJHak015577; Mon, 18 May 2020 07:19:17 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Mon, 18 May 2020 07:19:17 -0500 From: Segher Boessenkool To: Michael Ellerman Subject: Re: [PATCH v3] powerpc/64: Option to use ELF V2 ABI for big-endian kernels Message-ID: <20200518121917.GJ31009@gate.crashing.org> References: <20200429011959.1423180-1-npiggin@gmail.com> <87eerhagyd.fsf@mpe.ellerman.id.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87eerhagyd.fsf@mpe.ellerman.id.au> User-Agent: Mutt/1.4.2.3i 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: linuxppc-dev@lists.ozlabs.org, Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hi! On Mon, May 18, 2020 at 04:35:22PM +1000, Michael Ellerman wrote: > Nicholas Piggin writes: > > Provide an option to build big-endian kernels using the ELF V2 ABI. This works > > on GCC and clang (since about 2014). it is is not officially supported by the > > GNU toolchain, but it can give big-endian kernels some useful advantages of > > the V2 ABI (e.g., less stack usage). > This doesn't build with clang: > > /tmp/aesp8-ppc-dad624.s: Assembler messages: > /tmp/aesp8-ppc-dad624.s: Error: .size expression for aes_p8_set_encrypt_key does not evaluate to a constant What does this assembler code that clang doesn't swallow look like? Is that valid code? Etc. Segher