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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 54DEDC433F5 for ; Thu, 3 Mar 2022 14:41:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234137AbiCCOlr (ORCPT ); Thu, 3 Mar 2022 09:41:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234153AbiCCOlq (ORCPT ); Thu, 3 Mar 2022 09:41:46 -0500 Received: from mail-pj1-x1034.google.com (mail-pj1-x1034.google.com [IPv6:2607:f8b0:4864:20::1034]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C7D218F229 for ; Thu, 3 Mar 2022 06:40:59 -0800 (PST) Received: by mail-pj1-x1034.google.com with SMTP id ev16-20020a17090aead000b001bc3835fea8so5067575pjb.0 for ; Thu, 03 Mar 2022 06:40:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language :from:to:cc:references:in-reply-to:content-transfer-encoding; bh=w9SeCTTfPOMpZlaZeTxmD08SwR66pORbsklOSsmoU6E=; b=r+Ua4xpvDToaxfPBEdimELo/lWEwKUB7rJV8QX4scAoU+vh8Ym8nbc9lgHq8hSf5Hs y2fKbJgsUhuKelaHF9ulypRRVCxAcdOZ734pJAhmdy+/F/ow28XtMWe5dXvdLfxPCT8j RE5IVdy6Wl56FBdVwBVATY1B2SswlwHyszYG5PykyQOi2b432qvED/DKeklfQSBqwEbH J4gNAmFft/Ih1IN9BVxB4yUKzVEjt33MMwjQyYhVOVlEdnJky2O3opdnHyvhhoCRKQmx mdG8RBSWT0MHqSwkFM8WmxxM6SPkQZj2R0CruIRs/xUR+XAIZuGCXxaIHIRe87VzK7U0 oMSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:from:to:cc:references:in-reply-to :content-transfer-encoding; bh=w9SeCTTfPOMpZlaZeTxmD08SwR66pORbsklOSsmoU6E=; b=VgaS3ZCJGlteMlcQpT4E1I28D0XqIFXCq2MXafWzYYmFMx5UTaZwmcSi4Iz+AYxy5/ t4XvHQSgKwiJ08G9tlPKk6+/aX0ctceHXwg4qIyAc4OzJ7s1s3VpCnwZty03DfXy5hAo FVHzPY8eJNQxvAU61ssrNAOpOjNYQOnNqWnWsG9RVikO4DE8szC/UqqQVwgd6liBWy/A 2EiLnhhCHb8DY6Q+cuhKLszW88ZbeOF7aXFa86PS6y23KIzp4+U0Vkljuua8n0uuTMWG RPUHbnss55tLR+uhqhdkH1P5UUK3m4M9BSZWaNp0lTSq/hz8Vec9JjvP1uvoqhyPMZRV 9x3Q== X-Gm-Message-State: AOAM531MUnAFAiY9fsO2BoztZSIiv7dyrXo3zpAseTt4EH105/7N53WN tZD2+3j2T8WebZMSGzJPCsAV4FtqqKXfLw== X-Google-Smtp-Source: ABdhPJwpm6MyYPMj/oYwo7FlBVw3AHBHU1oUb1bPgpihsBw/T43geSOiyaIwaOcEkhzkALYTMAndIw== X-Received: by 2002:a17:902:7283:b0:150:b5b:5375 with SMTP id d3-20020a170902728300b001500b5b5375mr36581552pll.90.1646318455130; Thu, 03 Mar 2022 06:40:55 -0800 (PST) Received: from [192.168.1.100] ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id o3-20020a056a0015c300b004e17afd9af9sm2870249pfu.92.2022.03.03.06.40.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 03 Mar 2022 06:40:54 -0800 (PST) Message-ID: <040e9262-4ebb-8505-5a14-6f399e40332c@kernel.dk> Date: Thu, 3 Mar 2022 07:40:53 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH] io_uring: add io_uring_enter(2) fixed file support Content-Language: en-US From: Jens Axboe To: Xiaoguang Wang , io-uring@vger.kernel.org Cc: asml.silence@gmail.com References: <20220303052811.31470-1-xiaoguang.wang@linux.alibaba.com> <4f197b0e-6066-b59e-aae0-2218e9c1b643@kernel.dk> <528ce414-c0fe-3318-483a-f51aa8a407b9@kernel.dk> In-Reply-To: <528ce414-c0fe-3318-483a-f51aa8a407b9@kernel.dk> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 3/3/22 7:36 AM, Jens Axboe wrote: > The only potential oddity here is that the fd passed back is not a > legitimate fd. io_uring does support poll(2) on its file descriptor, so > that could cause some confusion even if I don't think anyone actually > does poll(2) on io_uring. Side note - the only implication here is that we then likely can't make the optimized behavior the default, it has to be an IORING_SETUP_REG flag which tells us that the application is aware of this limitation. Though I guess close(2) might mess with that too... Hmm. -- Jens Axboe