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 ED049C433E1 for ; Thu, 13 Aug 2020 20:37:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CA5A120716 for ; Thu, 13 Aug 2020 20:37:32 +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="xpmXjb8y" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726419AbgHMUhc (ORCPT ); Thu, 13 Aug 2020 16:37:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42684 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726384AbgHMUhc (ORCPT ); Thu, 13 Aug 2020 16:37:32 -0400 Received: from mail-il1-x143.google.com (mail-il1-x143.google.com [IPv6:2607:f8b0:4864:20::143]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53A54C061757 for ; Thu, 13 Aug 2020 13:37:32 -0700 (PDT) Received: by mail-il1-x143.google.com with SMTP id p18so2863249ilm.7 for ; Thu, 13 Aug 2020 13:37:32 -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=FqmAZYqzFsSkWzm5o6JzBWrR6k3tJqnevIJpVeNdzMc=; b=xpmXjb8yXTC+LVaZXU4TMn0MFpntrufP2lqe2nApiLUBxKdgpoEi9sHXKaiNHN/+i/ RxZEVsG1DSgXxXH+bSm0V/d+YsCwL5ejR+/2jIWDJhmE0zXD4t0yWiPhX4cWd7TkxxCh W8exrqh+T9poiNVKGVZHps2T4Y/cW2ZuhgmP+dFLEVvDM6FRFOIVj9RMgaTFL72BdZNq WoAWjYv9C/tB4xyHW2NKVz1syGQFfV0uEPjab4mw6ZgTohuQT+dDELdlyOKKIy0MnXHT pcLc+P8M/x+jZtkcnZUf3sz0UYlBeOZBMswpVEX1OYwjyrR4flc3+lIxv2v9FpAyCvWA k/Dw== 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=FqmAZYqzFsSkWzm5o6JzBWrR6k3tJqnevIJpVeNdzMc=; b=HwjwKJvWQpXeNuB/XMN3KDByk+Xt69FVElEpJ/EJLnJJHJmzwSyzrgm3efvu62WmMz G8y0/zXY0WXv9vcGYmjDrE3YUZB3UX4QuAGUwwQRdctFGCtbV3MUK4/ybqcaCZcsAdv0 YCfOcrmYksgiax4VWjB4ahKgl1AmC5gSSaMN70JALO/ilQvkfoSrH9e+5mAHWfQKIdzO pFvL1WC+MjVW1ZEb8LwRlDRrlFJRFd0KXRkXwxvXn2TWpzQMAdC1nsesmgbT48rxMZQs bR5cubKLE3QfY5IAG1h4c7aOQ5qfNdIucJQORD0y9EYAEYy3aJzSKP1mCd4lxXah3vta bihg== X-Gm-Message-State: AOAM532l0mZmhrmcQKAhYtKKnnxaXuIHXWgoBhjXxNHbxczR70Zocpne bKxrOYKpetxYf0IVU25ijYUnuvv39/U= X-Google-Smtp-Source: ABdhPJybe3xztlTAzs44jMd4bVx61FWHndqihrMhrJljmbtrlp1YmdyEjwGCj1sWaCqUvnYAatHRWQ== X-Received: by 2002:a92:dac1:: with SMTP id o1mr2583669ilq.86.1597351051693; Thu, 13 Aug 2020 13:37:31 -0700 (PDT) Received: from [192.168.1.58] ([65.144.74.34]) by smtp.gmail.com with ESMTPSA id f128sm3251731ilh.71.2020.08.13.13.37.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 13 Aug 2020 13:37:31 -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> Message-ID: <9f050b83-a64a-c112-fc26-309342076c71@kernel.dk> Date: Thu, 13 Aug 2020 14:37:30 -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: <99c39782-6523-ae04-3d48-230f40bc5d05@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 2:33 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? -- Jens Axboe