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=-3.7 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,MALFORMED_FREEMAIL, 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 22410C433DF for ; Tue, 13 Oct 2020 05:41:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C2C30208D5 for ; Tue, 13 Oct 2020 05:41:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="sCLwzONO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388098AbgJMFlo (ORCPT ); Tue, 13 Oct 2020 01:41:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38896 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732457AbgJMFlo (ORCPT ); Tue, 13 Oct 2020 01:41:44 -0400 Received: from mail-wm1-x344.google.com (mail-wm1-x344.google.com [IPv6:2a00:1450:4864:20::344]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFCB8C0613D0; Mon, 12 Oct 2020 22:41:43 -0700 (PDT) Received: by mail-wm1-x344.google.com with SMTP id k18so20425073wmj.5; Mon, 12 Oct 2020 22:41:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:in-reply-to:message-id:references :user-agent:mime-version; bh=d9vylN65+yzj7mksBEpuNNWYvYrmZ1UZPFWpzN8ZJnc=; b=sCLwzONOmV2FgbEAOU83au8Xo+dLKC7HW9WDa6LSVfMb9V8Jl4KZPyzFI3tycA7Khb sS2veNiS+XGL2ioy2cMAiCv/qr20FWJR7NpMlD42nbgcmRZdQePe/O5oOzromG/qMjoE gqRdNEtLex937a3wvsxc1jwF0tBMMwDefp/2oH0Y1Zdiw/JCZtVXH0XvOXof1JzDgYNh pnhtMM2uwTQpjO4oWYpG5lx1gZUF5W1Iz8uv0Rs4AZNVlnrgT+Y7bXld0EmyqEN9YsZZ qKrpj1SvtscbuMFaKUbvbWvfTqhTrQ1K8QHDwKRgVYCnowgZZBvPy/oPTF6fzx1jk5ku mSCQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:in-reply-to:message-id :references:user-agent:mime-version; bh=d9vylN65+yzj7mksBEpuNNWYvYrmZ1UZPFWpzN8ZJnc=; b=I9OZxsNrIgwYBX/4UBCIEwWg+Dg8QfFkzn2Tkj0mPT/KWHgVJwxvC50YsqpCfvzgMc mig6nnXyXAT8eO1pEBRlM3h+yDDEqGXc4dyR5TyrUwPUw2PO0NyAdUg6XVh9QCiPD5QQ jX4iaUVppWv39iaTGJY0+3GOLo9I1ifY/YEmdoulXMLzlE0a99g9OwKuD7oif9FGWfts IMlb7Psy1XepoLZrykHgi4IhIRbC+nwBz0nJDxfk0Bbc9Wrd8QsrX5lXv6BNVeIEOSBE 31bk3s13saYDEHBxq7wfULDwd/YYygyMaBGGrXytVkacwy8UWirVfQn+qm98RY8j91Ul CzZg== X-Gm-Message-State: AOAM530jfxb/F9nCYmqRNanx3MrEpuLTmOJT0BqG/dIB8sbyqjpVPr3z A28iDkDbey+Puy6xt87lPFIFamzD2D2MD7UO X-Google-Smtp-Source: ABdhPJyBxStNdGGvixqD19QWg9HaFQ15lb9VjTESTLLFfAXCJouGCu18qM+gVBG2G2S97MUHX7rWPA== X-Received: by 2002:a7b:c183:: with SMTP id y3mr13768508wmi.84.1602567702684; Mon, 12 Oct 2020 22:41:42 -0700 (PDT) Received: from felia ([2001:16b8:2d05:8100:95ae:bd1a:3e4e:4242]) by smtp.gmail.com with ESMTPSA id u2sm28834532wre.7.2020.10.12.22.41.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 12 Oct 2020 22:41:42 -0700 (PDT) From: Lukas Bulwahn X-Google-Original-From: Lukas Bulwahn Date: Tue, 13 Oct 2020 07:41:40 +0200 (CEST) X-X-Sender: lukas@felia To: Greg Kroah-Hartman cc: Lukas Bulwahn , Alan Stern , Sudip Mukherjee , linux-kernel@vger.kernel.org, linux-safety@lists.elisa.tech, linux-usb@vger.kernel.org Subject: Re: [linux-safety] [PATCH] usb: host: ehci-sched: add comment about find_tt() not returning error In-Reply-To: <20201013052150.GA330398@kroah.com> Message-ID: References: <20201011205008.24369-1-sudipm.mukherjee@gmail.com> <20201012145710.GA631710@rowland.harvard.edu> <20201012160013.GA632789@rowland.harvard.edu> <20201013052150.GA330398@kroah.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 13 Oct 2020, Greg Kroah-Hartman wrote: > On Mon, Oct 12, 2020 at 08:17:34PM +0200, Lukas Bulwahn wrote: > > > If you are suggesting some sort of special code annotation that the tool > > > would understand, I am open to that. But I'm not aware of any even > > > vaguely standard way of marking up a particular function call to > > > indicate it will not return an error. > > > > I cannot yet say if some annotation would work, we, Sudip and me, need to > > investigate. It could be that something like, assert(!IS_ERR(tt)), is > > sufficient to let the tools know that they can safely assume that the > > path they are complaining about is not possible. > > > > We could make the assert() a nop, so it would not effect the resulting > > object code in any way. > > Things like assert() have been rejected numberous times in the past in > the kernel, good luck with that :) > Greg, we have been warned by you now; so, we are well aware what could await us just as numerous others before. Lukas