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=-5.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,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 A0949C4707F for ; Tue, 25 May 2021 22:28:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6D9FC613FA for ; Tue, 25 May 2021 22:28:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231134AbhEYW3x (ORCPT ); Tue, 25 May 2021 18:29:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42836 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230313AbhEYW3x (ORCPT ); Tue, 25 May 2021 18:29:53 -0400 Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B78AC061574 for ; Tue, 25 May 2021 15:28:23 -0700 (PDT) Received: by mail-pj1-x1033.google.com with SMTP id m8-20020a17090a4148b029015fc5d36343so70753pjg.1 for ; Tue, 25 May 2021 15:28:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=x9qwPWMfCgzIMftuDjXnPzMh23kCj3dHIBBRGTms0Jo=; b=ZOOEBB7z57v74LWT0rNZOfqmfFcW5pA9QsVwvpzDGZbRTGYlmZoOgndvUubtpxN5NC pKV0T9ERitQWLHphZ1GgAZR1F5TyjDY2Tqschi0+V6EW9FpRqADKpsovbbGC8TVHsx4J NYOuO/JMdahwN7crgpiIjeuTRgZkoY2nLJEQH5KiESfwEDWK7TysKdTEEFJfV7xyC1eT VRJcb7VPI+X+I3CjTKt+fpj7vHEZmrU5oGu5VvGEXvQyDjt2N25IIYt7AH7Ukp3eHtAF LSpc4ZPk7wRGGRFbVWcxoQPA9INK0wQipRnc+vvS+E/z9zsWFddk/5gVPVXqvWh93M/I NqQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=x9qwPWMfCgzIMftuDjXnPzMh23kCj3dHIBBRGTms0Jo=; b=kVh/CsV4I3a1ewZV8064ArZ69MXLxjFrI9XxFiiOnZgDbijPumJQcMPSEk5Erjxie6 LPQH7XcIrxF4NArCvNFX07ILeTI/KWfLLOUFLMNO21OyGk50pFgIyc8R59mR7J02QoeM /+5isanHjg3OBfSrRUPRC9qB+msad5LeDKwZhoBXPiniWdDlMhjFCmkUeUwyKtLs2seu txxti+cF7GuChCpUa57eXTTjulI+KlISfp9SFywML1qoNpYktv/AxR3cv1SeOmseO9N4 pqXSyZeK3U0X5EAG0e/8lnq9PoNDFBChyt8bf9nhQ93p0j689H6FdFUc+uc3W2ltt4nZ ph/A== X-Gm-Message-State: AOAM530uz5gmWX2huOnTxUqUE9LPRVAzHRlA1g2DojUyzP25HH2f1fLL q2cV8/qXNSZVpTbYspQNr5mNlQ== X-Google-Smtp-Source: ABdhPJyZvGUX1TrZ3jandii3/ind0Kb0sNnZcjf1q2lvaVZKJ+PwnwV1j+PSVr6J61G7cCYME+YScw== X-Received: by 2002:a17:90a:fe02:: with SMTP id ck2mr32982813pjb.173.1621981702443; Tue, 25 May 2021 15:28:22 -0700 (PDT) Received: from [192.168.1.134] ([66.219.217.173]) by smtp.gmail.com with ESMTPSA id w19sm13591843pfu.215.2021.05.25.15.28.21 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 25 May 2021 15:28:21 -0700 (PDT) Subject: Re: [PATCH] io_uring: Add to traces the req pointer when available To: Olivier Langlois , Pavel Begunkov , Steven Rostedt , Ingo Molnar , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org References: <60ac946e.1c69fb81.5efc2.65deSMTPIN_ADDED_MISSING@mx.google.com> <439a2ab8-765d-9a77-5dfd-dde2bd6884c4@gmail.com> <2236ed83-81fd-cd87-8bdb-d3173060cc7c@gmail.com> <6133244fb6181420b27694abdfe3f42d43df8868.camel@trillion01.com> From: Jens Axboe Message-ID: <5fb15014-94ba-e0ca-fa13-f9e898824185@kernel.dk> Date: Tue, 25 May 2021 16:28:20 -0600 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: <6133244fb6181420b27694abdfe3f42d43df8868.camel@trillion01.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 5/25/21 3:48 PM, Olivier Langlois wrote: > On Tue, 2021-05-25 at 17:26 -0400, Olivier Langlois wrote: >> but the pointers should be hashed by trace. >> >> That would be nice if someone more knowledgeable about the tracing >> system could jump in and comment about the hash-ptr option and tell >> when it is applied and when it is not... > > My concern about hashing pointers directly in the io_uring code > directly. It is that by doing so will make it impossible for a > sufficiently priviledged user to get the raw pointer values without > reverting back the pointer hashing stuff. > > that would not be the right way to address the security concern if the > tracing subsystem already hash them by default and is configurable to > display raw pointers if desired. > > My issue is that I haven't been able to see hashed pointers output from > trace. Just a quick guess, but does it rely on using %p to print the pointers? -- Jens Axboe