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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 78325C32751 for ; Wed, 31 Jul 2019 04:13:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 48D9A2067D for ; Wed, 31 Jul 2019 04:13:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="r1wIjjla" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727725AbfGaEND (ORCPT ); Wed, 31 Jul 2019 00:13:03 -0400 Received: from mail-qk1-f195.google.com ([209.85.222.195]:33071 "EHLO mail-qk1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725970AbfGaENC (ORCPT ); Wed, 31 Jul 2019 00:13:02 -0400 Received: by mail-qk1-f195.google.com with SMTP id r6so48273457qkc.0 for ; Tue, 30 Jul 2019 21:13:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=NFVesl0ZnOpQBqtMqV5lpfo1vwR6WRneLNekq2w+A+0=; b=r1wIjjlaOUYXC9i0CtRzf8gVkGR6i7HDy0I7VVJKls8IoU+bJTFRBj1qe/DGeZNwS3 mgGjvWiGMKJ5bP8brcspcZO4X4V9eenYomQN3tD6rEkVc0vAb+6ZpUSxr5z+Ixu7M5LS C+dQ4sCispoR+WPJbpeV4A3KmqkmKV8aNcP8bUq37kWCpCN8HmKmrmVc8vrmnmmS5a1z pllvWFZjj4465RcciKSuD8r9iNFT9t0DU+fajvZmzT+qVTZnQCeDyTZZLsYvTPcta7Vy 4NaCttjGVF1oboy6iznh59NugAeylu++kg+f7wcyJVdYPc0G39Hhm3wTwrIOxZ+x8oOL cRHA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=NFVesl0ZnOpQBqtMqV5lpfo1vwR6WRneLNekq2w+A+0=; b=DCnTqnMdb8WX/NLn5qvdUkxc1RpiAUsVpMA/1C13IudOQnSlGgC9wXole3ZnzqUdl6 3jlD7/IwofugdPmzoc9dSOeVqnH5HGJUqp1H8mxfWBzT/4WknsLLgXzZA7AgkZsH6fAj iIOjVI/DZWs0RO5kKUefvnCCSpQvKb2AnoWx1T4J1ykbHJ1+bwlb2k+zrle8zFwFlx7x UmAzmJBpdw143ElLDo2AZlqLJ7SH1Gx6QrGRF1X2ssq7p64iX1hBJqT0NluLnutVsuZw pTFKSeEti2JPXmaRUJDaMCt+RstVnRLv+mo6yVhqek4fXunsNYFQveguo3Q76wIrPHKE pnHg== X-Gm-Message-State: APjAAAUMyXKVhT7la54ZK4CHDmbDsmV2i0jkCQbFe88y3OtnNIqZW6yr UDiQ3jnI4KpUvN3/vADLhpMPbbZLmanqfy7XgyfToUN9 X-Google-Smtp-Source: APXvYqy2sz2eWCGTJfeBDvYeHklxGvXDMSeWgw1gHMMJZXav5IjX+rI/W8oAUPJin0pn2pg2QXOlbRH7FD1Tuk2ix2k= X-Received: by 2002:a37:5942:: with SMTP id n63mr5572295qkb.69.1564546381707; Tue, 30 Jul 2019 21:13:01 -0700 (PDT) MIME-Version: 1.0 References: <20190730044326.1805-1-luaraneda@gmail.com> <20190730104746.GA1330@shell.armlinux.org.uk> In-Reply-To: <20190730104746.GA1330@shell.armlinux.org.uk> From: Luis Araneda Date: Wed, 31 Jul 2019 00:12:11 -0400 Message-ID: Subject: Re: [RFC PATCH] ARM: zynq: Use memcpy_toio instead of memcpy on smp bring-up To: Russell King - ARM Linux admin Cc: Michal Simek , linux-arm-kernel , linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Russell, Thanks for reviewing. On Tue, Jul 30, 2019 at 6:47 AM Russell King - ARM Linux admin wrote: > > On Tue, Jul 30, 2019 at 12:43:26AM -0400, Luis Araneda wrote: > > This fixes a kernel panic (read overflow) on memcpy when > > FORTIFY_SOURCE is enabled. [...] > > I'm not convinced that this is correct. It looks like > zynq_secondary_trampoline could be either ARM or Thumb code - there is > no .arm directive before it. If it's ARM code, then this is fine. If > Thumb code, then zynq_secondary_trampoline will be offset by one, and > we will miss copying the first byte of code. You're right, I tested what happens if the zynq_secondary_trampoline is ARM or Thumb by editing the file where it's defined, headsmp.S When the .arm directive is used, the CPU is brought-up correctly, but if I use .thumb, I get the following message (no panic): > CPU1: failed to come online This seems unrelated to solving the panic, as the message even appears with memcpy and FORTIFY_SOURCE disabled. I could add the .arm directive to headsmp.S Is that your expected solution? Should that change be on a separate commit? I'd like to know Michal's opinion, as he wrote the code.