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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 51070C33C9E for ; Wed, 29 Jan 2020 00:20:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 20D6D21739 for ; Wed, 29 Jan 2020 00:20:04 +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="r0kpkmQn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726402AbgA2AUD (ORCPT ); Tue, 28 Jan 2020 19:20:03 -0500 Received: from mail-pg1-f180.google.com ([209.85.215.180]:33553 "EHLO mail-pg1-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726293AbgA2AUD (ORCPT ); Tue, 28 Jan 2020 19:20:03 -0500 Received: by mail-pg1-f180.google.com with SMTP id 6so7908908pgk.0 for ; Tue, 28 Jan 2020 16:20:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=8kyp/VrhKERhG+K9hmS2Utzgr/wVLR2b6aoPqZM79B8=; b=r0kpkmQnfZmk9IbPJO4MAEgMnD2y/qsDQvmgioR/iMb4vvB/K8JRT1+0ktFzm2jpPK VKX9vXncytbjxDo0X/4a7CKFfOZrFk78e1xncDUYVSeokq3c2zX3wwvZ20AoIdH6RtbR o+eq7J6JmE7m1cU/CfOzTONCCdu+/XaJcg1Q33sp5B3RgjQiwLIby2YQp0ijAe1CZW0w n26pZBYIQ8GP7Qa8tirpkEKdaZOipH0R0rQlRoV4J31HunXjSpBIQBNaWIJgZ4gvGU3+ KGGj2h8kMovtRqeN46OoQOCB3pK7HwJ8SkSsGFM0x4sL8xbEUiVstCG27ukIcdTUPhAi o8FQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=8kyp/VrhKERhG+K9hmS2Utzgr/wVLR2b6aoPqZM79B8=; b=CEwFlBmX0kYTi5rgE3xiXCWRVcCdcL04ZZ/UjruMRpl43W++xkfuuCdJuUh0oGAuCv oUo6p06Bv+XToveOtXUFk7EvcITlbJN+WzbuAfzCVtMV+SoDO+6wczAuuzj2U56k+G7Q I5K4+erw0C7dFqk0sbt3IyXSZ979v+y+psgHpACo+o7WJiopV8Wf5mLX8hNLIWSx3XFV UdCg0HDmD+tNefTHnA89cv02iQUOZQXM5VQ6M+WJyFGYVBbRPhgRgKDxzp+722xMIg1U g6ro4cWGiWIvc2bscKIR00UgHxcd+/ZKRZ8OZUWn6S9J3boQdXWJxpPU3wraisDxRiSy ijHg== X-Gm-Message-State: APjAAAXUYkQb7bXzJLDsYd9YAvc6Ff3PDzCx1oa1PfwLUnfZ3/bO8ray 8P7aZP7qtkJl8GzXsRDpFDXqwA== X-Google-Smtp-Source: APXvYqxj/VTK9uE+Yaw3RPpOWhOxp4InAorRUcwedVhsztPskMNJGVyfs9h+72dJLxMSsxQvo1THTw== X-Received: by 2002:a63:5d4d:: with SMTP id o13mr26855190pgm.182.1580257202717; Tue, 28 Jan 2020 16:20:02 -0800 (PST) Received: from [192.168.1.188] ([66.219.217.145]) by smtp.gmail.com with ESMTPSA id x65sm186209pfb.171.2020.01.28.16.20.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 28 Jan 2020 16:20:02 -0800 (PST) Subject: Re: IORING_REGISTER_CREDS[_UPDATE]() and credfd_create()? To: Pavel Begunkov , Stefan Metzmacher Cc: io-uring , Linux API Mailing List References: <688e187a-75dd-89d9-921c-67de228605ce@samba.org> <1ac31828-e915-6180-cdb4-36685442ea75@kernel.dk> <0d4f43d8-a0c4-920b-5b8f-127c1c5a3fad@kernel.dk> <2d7e7fa2-e725-8beb-90b9-6476d48bdb33@gmail.com> <6c401e23-de7c-1fc1-4122-33d53fcf9700@kernel.dk> <35eebae7-76dd-52ee-58b2-4f9e85caee40@kernel.dk> From: Jens Axboe Message-ID: Date: Tue, 28 Jan 2020 17:20:00 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: 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 1/28/20 5:10 PM, Pavel Begunkov wrote: >>>> Checked out ("don't use static creds/mm assignments") >>>> >>>> 1. do we miscount cred refs? We grab one in get_current_cred() for each async >>>> request, but if (worker->creds != work->creds) it will never be put. >>> >>> Yeah I think you're right, that needs a bit of fixing up. >> > > Hmm, it seems it leaks it unconditionally, as it grabs in a ref in > override_creds(). > We grab one there, and an extra one. Then we drop one of them inline, and the other in __io_req_aux_free(). -- Jens Axboe