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 CAF48C43334 for ; Sun, 17 Jul 2022 20:29:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232361AbiGQU3a (ORCPT ); Sun, 17 Jul 2022 16:29:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232120AbiGQU33 (ORCPT ); Sun, 17 Jul 2022 16:29:29 -0400 Received: from mail-ed1-x52d.google.com (mail-ed1-x52d.google.com [IPv6:2a00:1450:4864:20::52d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B057C2640 for ; Sun, 17 Jul 2022 13:29:27 -0700 (PDT) Received: by mail-ed1-x52d.google.com with SMTP id t3so12926873edd.0 for ; Sun, 17 Jul 2022 13:29:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=a5n4kSbt+tDnJOmMOFdBXx2xa6DkOaFuSU52FmmeggU=; b=aJ0ySncRL5xwy3/WJRusOdK8nCOceATdsP/LrESQ+9olCuwbS7L0orcpD4kg4D4J+f KbkqgAwS/00KYAzWOUWUp64AdQklzywMgBC25bxwJEUp2t8R4RI5hI6drZwEdRnOVoxi fCWhU2soygB4BoKsZzC3n71dPyEKBWfwoYlmg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=a5n4kSbt+tDnJOmMOFdBXx2xa6DkOaFuSU52FmmeggU=; b=0VyMTm0qegzYamgnejxMbDKqlm4yWiwUzrLvY2DpXxMuEenyX3GKSt9C/Y1BtDbSMP ZTr8RYDGtdiyJl7rXh+TDDiboxT/zeVWz8CLzI55N1/QzlF/Z4bzR+srdk0vPSmp3a8m JNbud+u/vxEgAWPpIOLTeYVRYjCRJiBOxqnLLSeaMXNnqgBuKXnHX612xZTStgchbQxm bvwwNaPwCON3y7UZqJGSNZPekpZyaSFWN3ObefF02vJunn03xfzxAdf/4c2q8sgCF6If YNAwljcV/hRQnJ5UkMVs9QktDRah/3aIvWG8nzFHd8uCGKGBFpaWATFwmbSCIkj+VzPi BiKQ== X-Gm-Message-State: AJIora8e2viN7HHffd/jHziQsTSMykBdWpD3WucXCYqj7SciQkW6zdvv pq+L9mCnbNfq3YLcFATWBqIrSCNLd2Y0Do8AWQ0= X-Google-Smtp-Source: AGRyM1tUHkQxEkjsVydKlHpCXkRdknDbstXuW+Pxxj+/fT1bDlHHcDVshc/vYag+/duQcIl1vpD/3g== X-Received: by 2002:a05:6402:3202:b0:43a:86f5:a930 with SMTP id g2-20020a056402320200b0043a86f5a930mr32462371eda.389.1658089766109; Sun, 17 Jul 2022 13:29:26 -0700 (PDT) Received: from mail-wr1-f52.google.com (mail-wr1-f52.google.com. [209.85.221.52]) by smtp.gmail.com with ESMTPSA id r18-20020a17090609d200b006feed200464sm4651872eje.131.2022.07.17.13.29.24 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 17 Jul 2022 13:29:25 -0700 (PDT) Received: by mail-wr1-f52.google.com with SMTP id r2so13460390wrs.3 for ; Sun, 17 Jul 2022 13:29:24 -0700 (PDT) X-Received: by 2002:a5d:69c2:0:b0:21d:807c:a892 with SMTP id s2-20020a5d69c2000000b0021d807ca892mr20430637wrw.274.1658089764088; Sun, 17 Jul 2022 13:29:24 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Linus Torvalds Date: Sun, 17 Jul 2022 13:29:07 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: mainline build failure of powerpc allmodconfig for prom_init_check To: Sudip Mukherjee Cc: Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Kees Cook , linuxppc-dev , linux-kernel , linux-hardening@vger.kernel.org, Segher Boessenkool Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 17, 2022 at 1:25 PM Sudip Mukherjee wrote: > > And the generated assembly still has the memset for "struct prom_args". Strange. That smells like a compiler bug to me. But I can't read powerpc assembly code - it's been too many years, and even back when I did read it I hated how the register "names" worked. Maybe it was never the args array, and it was about the other fields. Not that that makes any sense either, but it makes more sense than the compiler turning a series of volatile accesses into a memset. Linus