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=-5.5 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 E03D4C433E1 for ; Thu, 13 Aug 2020 20:41:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A6AC62078B for ; Thu, 13 Aug 2020 20:41:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="NDq+UwTk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726419AbgHMUlk (ORCPT ); Thu, 13 Aug 2020 16:41:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43310 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726312AbgHMUlj (ORCPT ); Thu, 13 Aug 2020 16:41:39 -0400 Received: from mail-io1-xd2d.google.com (mail-io1-xd2d.google.com [IPv6:2607:f8b0:4864:20::d2d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7595AC061757 for ; Thu, 13 Aug 2020 13:41:38 -0700 (PDT) Received: by mail-io1-xd2d.google.com with SMTP id q75so8789181iod.1 for ; Thu, 13 Aug 2020 13:41:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:from:to:cc:references:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=JeKQEIsI+m9lrsQ8N8j8sbWZddsLa5CFhrA4d9dQeLo=; b=NDq+UwTkosKhP7HkcZFmBcOfzPR63twihNpX6rtHNW0eBEwFhQM/O5+g+N3HwF41QC +f2f/KlwCVIn7TqydFPFpXeNOHZqcdHavJlojRuflUlJkzOLmeiy2jjUrOyFEns66A4y kZy/nRZHWLz+bfAtChSuZTKA3OQU5cHGvxGfZYkvwN89DNWupq9u/MHM2E5jS0pZBMgp B+dN9w5A6zraDsuRobK+FHvZgaJBKDX7Icga0TCYzhWY7/tJPdXSMtWcoLvD94AuXiUF Gss/yvtAQgKgCEaTaPjTQYjNNx9W6B0KiW9uzqs4WOChlOFB/2rRE/8qdrCySMp4Awwr 2l2Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=JeKQEIsI+m9lrsQ8N8j8sbWZddsLa5CFhrA4d9dQeLo=; b=mW9fGek5SdLC7zjLVXH5dCt6XVTKpPQnUOF1gq9L0pttRQhzcYb0+cOYKHDcAxFdq0 mn+E/m9Nzvzoy5jjK406V7Y0BtFG1Kix6J7zHSt9KqZLerh64ZmdkibrPbAnG/Um2b6H Z2LB7d6UQTi+ftv4y9RuJqUE4Rhsa6afRN9Vbv3nIlvj1KZD4GuU8Dmdbhhe0MM2Z3iG dY+31hYgczreXQcHhlKyabdGPQE9cg5EtNj8ypOw/C9NI1tCJjZle9jPt/7qhr6Taxhh 0JcZf/iMJ9JdS5IwF6IQ7MDgbwx6KiQhkcjOf5t4fhP9gSATD2Tsqh3EfJZTUjpayHiI FWVQ== X-Gm-Message-State: AOAM531hLsryOYiGYsiusBsngys/NC3wm8B93HEtW/6bv8l6LHYeIK9w MeHLK0ELNffOGCne5IemFF+0fQ== X-Google-Smtp-Source: ABdhPJxcuwniyK0QJ2qWqvncd6aXPLBF4/5KaSXjOaTMM6Gvhfu822bhzzigBgmcGCDTE6xi79IH/w== X-Received: by 2002:a05:6638:13c5:: with SMTP id i5mr6798299jaj.29.1597351297466; Thu, 13 Aug 2020 13:41:37 -0700 (PDT) Received: from [192.168.1.58] ([65.144.74.34]) by smtp.gmail.com with ESMTPSA id 25sm3430538ilv.85.2020.08.13.13.41.36 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 13 Aug 2020 13:41:37 -0700 (PDT) Subject: Re: [PATCHSET 0/2] io_uring: handle short reads internally From: Jens Axboe To: Jeff Moyer Cc: io-uring@vger.kernel.org, david@fromorbit.com References: <20200813175605.993571-1-axboe@kernel.dk> <99c39782-6523-ae04-3d48-230f40bc5d05@kernel.dk> <9f050b83-a64a-c112-fc26-309342076c71@kernel.dk> Message-ID: Date: Thu, 13 Aug 2020 14:41:36 -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: <9f050b83-a64a-c112-fc26-309342076c71@kernel.dk> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 8/13/20 2:37 PM, Jens Axboe wrote: > On 8/13/20 2:33 PM, Jens Axboe wrote: >> On 8/13/20 2:25 PM, Jeff Moyer wrote: >>> Jens Axboe writes: >>> >>>> Since we've had a few cases of applications not dealing with this >>>> appopriately, I believe the safest course of action is to ensure that >>>> we don't return short reads when we really don't have to. >>>> >>>> The first patch is just a prep patch that retains iov_iter state over >>>> retries, while the second one actually enables just doing retries if >>>> we get a short read back. >>> >>> Have you run this through the liburing regression tests? >>> >>> Tests failed >>> >>> I'll take a look at the failures, but wanted to bring it to your >>> attention sooner rather than later. I was using your io_uring-5.9 >>> branch. >> >> The eed8b54e0df-test failure is known with this one, pretty sure it >> was always racy, but I'm looking into it. >> >> The timeout-overflow test needs fixing, it's just an ordering thing >> with the batched completions done through submit. Not new with these >> patches. >> >> The read-write one I'm interested in, what did you run it on? And >> what was the failure? > > BTW, what git sha did you run? I do see a failure with dm on that, I'll take a look. -- Jens Axboe