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=-4.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,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 A9BCBC48BDF for ; Sun, 13 Jun 2021 20:07:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7AB706124B for ; Sun, 13 Jun 2021 20:07:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231840AbhFMUJ1 (ORCPT ); Sun, 13 Jun 2021 16:09:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231788AbhFMUJZ (ORCPT ); Sun, 13 Jun 2021 16:09:25 -0400 Received: from mail-pg1-x52f.google.com (mail-pg1-x52f.google.com [IPv6:2607:f8b0:4864:20::52f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8A75CC061574 for ; Sun, 13 Jun 2021 13:07:12 -0700 (PDT) Received: by mail-pg1-x52f.google.com with SMTP id e20so7028642pgg.0 for ; Sun, 13 Jun 2021 13:07:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=CiYUu2FG3HzlT4zH2YA+/ZlUCQRb2ZZzkBuzJ9thcHg=; b=Op9BchT98Ekvvq5+yFv1Av9v0Jsvab6N6w0bAH3htrMV5ViJeJD/jRzt34gMtrSCM0 k7uFGICDhkWzbAu6cgXVcQGm84zYmOvEVU/tL8yq38HUF1+yTYmCKn3KvNgl6ldTScrW VdjSMM25ySwQGpDcP6nEkel71pEG0qToc2XoEZ4uMrZRz34ToIML2T51ea1rfpn7UTF0 6PPT52qbMJuG7W8Iuu22fDNmxrgvitywUdxQ7MISQaBZ+oldlwlcrvflJZYKCRTijhzo SafI+uom8LsXetk3rHLP5tvpmAKWkbQN1IUAWr7gl1Ho+TSLPL72c0D5JlGyL5upUmWl AXMw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=CiYUu2FG3HzlT4zH2YA+/ZlUCQRb2ZZzkBuzJ9thcHg=; b=Cs2AdtFxJn4QX2UUYm0ESvoXozQiTCQKe57RMK/MyvtHs6XptVwlGEVVljChSaZYzL rpSU6i+3m4ofSWxGGuiy0IYbE8RmIGDRlquCa1JlV9YooE5oYVwZXQkZqzf/9CF6in+M yU1/etLyVrp9KGQWYC+7YBO/G74rkfQXe4ZzuQ5544ClnSnblUWNZRP4FPBuzYQJ1qtA O0hWWoN4RhkmWxzu1vmwUlsOQKJ5WwWDQiJ+9qh0MZSBcCnXCCX0I3nh3bmuYntJsZiD Ap7cKIb8TS2/B1jQPTYBZqHhDZW4R0lvEFfrPZSsNqsO5ncrMV8625b+ghrs+oPBSsrf PY2A== X-Gm-Message-State: AOAM532i5jn507BlP7v8tZugXQSDn69iUVPIkA0Ots+61AxtpgM7paoz 4i6LKuJx4A29SQCekJo+cCJ7eY5Nim0= X-Google-Smtp-Source: ABdhPJxVv3j/WmRjOoDTnHDBtdomBVwPGG3nD+/7czESMQbGqO8x8E+Gk7crhOCw4zixdDZhArRljg== X-Received: by 2002:a63:544e:: with SMTP id e14mr14029347pgm.256.1623614830860; Sun, 13 Jun 2021 13:07:10 -0700 (PDT) Received: from ?IPv6:2001:df0:0:200c:9034:3fbe:cf28:988a? ([2001:df0:0:200c:9034:3fbe:cf28:988a]) by smtp.gmail.com with ESMTPSA id p11sm10180026pfo.126.2021.06.13.13.07.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 13 Jun 2021 13:07:10 -0700 (PDT) Subject: Re: [PATCH v1] m68k: save extra registers on sys_exit and sys_exit_group syscall entry To: Linus Torvalds Cc: Geert Uytterhoeven , linux-arch , linux-m68k , "Eric W. Biederman" , Andreas Schwab References: <87sg1p30a1.fsf@disp2133> <1623541098-6532-1-git-send-email-schmitzmic@gmail.com> From: Michael Schmitz Message-ID: <0a96ad37-dedb-67f3-3b27-1ff521c41083@gmail.com> Date: Mon, 14 Jun 2021 08:07:04 +1200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org Linus, On 14/06/21 7:59 am, Linus Torvalds wrote: > On Sat, Jun 12, 2021 at 4:38 PM Michael Schmitz wrote: >> do_exit() calls prace_stop() which may require access to all saved >> registers. We only save those registers not preserved by C code >> currently. >> >> Provide a special syscall entry for exit and exit_group syscalls >> similar to that used by clone and clone3, which have the same >> requirements. > ACK, this looks correct to me. > > It might be a good idea to generate a test-case for this - some > "ptrace child, catch exit of it, show registers" kind of thing - just > to show what the effects of the bug was (and to show it's fixed). But > maybe it's not worth the effort. I'd love that, too. My test rig doesn't allow dumping of registers by strace, but someone else may have that capacity. Cheers,     Michael > > Linus