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 A6FA2C433F5 for ; Fri, 7 Jan 2022 16:23:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232495AbiAGQXP (ORCPT ); Fri, 7 Jan 2022 11:23:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41780 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231599AbiAGQXP (ORCPT ); Fri, 7 Jan 2022 11:23:15 -0500 Received: from mail-ed1-x52c.google.com (mail-ed1-x52c.google.com [IPv6:2a00:1450:4864:20::52c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11818C061574; Fri, 7 Jan 2022 08:23:15 -0800 (PST) Received: by mail-ed1-x52c.google.com with SMTP id u25so24150173edf.1; Fri, 07 Jan 2022 08:23:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=7ksVNQ+2KGXbOrVS8Wvzq1UTTH4v+seanY4gowafB9k=; b=fHCJR5cZeorxot9V7bzo9/Y6XvMMTmjmaFV//hLEL183Pu2SYBDs+bzSwkd4dCd9RB N878Y6mY/7p6gR5hRcQ9C6CHxod/Fb24BXLnD2rdXh2FAziT5IfsljnNrSTCsHi0U1zx HimCq9owjeS58+e0sgzgo8VPLR8DgbEv4TBN7fF1PrlAN1EIg3U9t60c55jCGnB8ITvO AFOYlMrY3W94jAqbg6oKGw3mzgvnOCTPrEzkVLQ0sThGlLEKDsejPPxChT0KcHrUDHKD UOph2yKcAlm1apDhPF0kp5IVBkz1NM2vZqHPoMcw8jhmjctTIANoYTChBcCYyjymPJNA Xu6w== 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:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=7ksVNQ+2KGXbOrVS8Wvzq1UTTH4v+seanY4gowafB9k=; b=rz3t9j1Bdbzo4HDJsCCSZPY4mQZk8sa4VpdD5mSOIxodWkxiLTEosAXDw1ebLtVYwn kAjcJDtQd6ewfD01c6Sqn3OlkB+v4u+qyCaFibph++94F9CUVoJVix9ExE6FI3FJYi1T yQmP4zFcTd5VrHEojmRAQjMvq5ug1AAwD2mH6TzkKIxHH1oSOJw6X0hfhhocv3t0AziL F+mPDrieoGWR4t0mKnqSCAFnzObW2AGIAOFQmC5LKkeC7RNM4ab+mySK8RniatITE2h6 vKLbS8EkdJ40FGoHw3kynARLmmlZH6rpyb+/OVbT/dt9gusb11oYYpsRys4Vd++iqFc3 pmmQ== X-Gm-Message-State: AOAM530IYtolaopAtMBtpfUfYa3n2y+uJPoR6P8OHNMB+6EqM6FIWcqn 4pcGfKn37ZBC8ccAMpxdQag= X-Google-Smtp-Source: ABdhPJzcuXRWso/d6jreO6uu/Rv9QdY34wlneTJLzuyx+U+n3mMypmDrYbBk5aX++QSNQI3o9tyfDA== X-Received: by 2002:a17:907:c17:: with SMTP id ga23mr46416747ejc.127.1641572593653; Fri, 07 Jan 2022 08:23:13 -0800 (PST) Received: from [192.168.8.198] ([148.252.128.4]) by smtp.gmail.com with ESMTPSA id 16sm1527241ejz.34.2022.01.07.08.23.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 07 Jan 2022 08:23:13 -0800 (PST) Message-ID: Date: Fri, 7 Jan 2022 16:22:44 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.4.1 Subject: Re: Observation of a memory leak with commit e98e49b2bbf7 ("io_uring: extend task put optimisations") Content-Language: en-US To: Lukas Bulwahn , Jens Axboe Cc: Linux Kernel Mailing List , io-uring@vger.kernel.org References: From: Pavel Begunkov In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 1/7/22 15:00, Lukas Bulwahn wrote: > Dear Pavel, dear Jens, > > In our syzkaller instance running on linux-next, > https://elisa-builder-00.iol.unh.edu/syzkaller-next/, we have been > observing a memory leak in copy_process for quite some time. > > It is reproducible on v5.15-rc1, v5.15, v5.16-rc8 and next-20220106: > > https://elisa-builder-00.iol.unh.edu/syzkaller-next/crash?id=1169da08a3e72457301987b70bcce62f0f49bdbb > > So, it is in mainline, was released and has not been fixed in linux-next yet. > > As syzkaller also provides a reproducer, we bisected this memory leak > to be introduced with commit e98e49b2bbf7 ("io_uring: extend task put > optimisations"). > > Could you please have a look how your commit introduces this memory > leak? We will gladly support testing your fix in case help is needed. Thanks for letting know I think I know what it is, will get back later. -- Pavel Begunkov