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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 EDB0EC43603 for ; Sat, 7 Dec 2019 04:01:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B6A32206D6 for ; Sat, 7 Dec 2019 04:01:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575691311; bh=joy/B5/1KS6PV1WRE8tFHoiMElRANVZfYceAXfaRVac=; h=References:In-Reply-To:From:Date:Subject:To:List-ID:From; b=baU8QCxgLEQnGExAr7/WvaAiZXzXIdNrFSaRG+SZUdJbEdEw0tmfazCIDW9KTcNvQ mciETtV4CVBY2PhV9SaiSsO6D3Gxu1WGUikIRyNfk1Zl2LUfAZTmCcVhIfe/iR9jO/ 3xJaYt0J8WXratOLlQzGDoWv5khokYHIVXCV4sNg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726509AbfLGEBu (ORCPT ); Fri, 6 Dec 2019 23:01:50 -0500 Received: from mail-lj1-f195.google.com ([209.85.208.195]:35190 "EHLO mail-lj1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726371AbfLGEBu (ORCPT ); Fri, 6 Dec 2019 23:01:50 -0500 Received: by mail-lj1-f195.google.com with SMTP id j6so9827283lja.2 for ; Fri, 06 Dec 2019 20:01:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=D9bKHIb2A+ygTSdf7+zChgWhyt6dX/dK0jQhf4W59Is=; b=VewXPpWS3+yURzc9MxeOz56Shx1+ekHKKsZfJnkLg9gHFEScXDb5QEN818XuMQTXYe NyJTv407dJJ9d7NrQabS6rsC/IYYbwFbxjny2fxTVVGjPfxy1f48xIkLhmJy8IQJILgZ BI217t4bFVF2NVTgqWRTPYknLUJ/qIOuDYDFk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=D9bKHIb2A+ygTSdf7+zChgWhyt6dX/dK0jQhf4W59Is=; b=fc5LutpoSvuIT+UC5RxVGrIcRtAW3uK4xC3NMIx1W/U7J0vwB85PQqVSkfIFG+An9K 9X5GEtvNDqbKjJUxJgUIAnmymHiy7f3sETzuApuiVRjvacmg5WdEVVG4PbiQh83MNwQN rwv2jyoitaayuj6Sfo7r5WRKHWbnK1QhOb87mAhBufb21zo/r+nVkuZVy7DIVACj42IU ai9Cb0Ty3gn3/fPPAAOh2rD8gEnFN27Mz5CxZr/Kvz1vyz5vgmXIQrWlDzigcJrnxKm5 /qKDnT2J1q44/+8i4TuOgpT6l0DHwvWFnC6WNJxoAEo4c7QHhSwBFoRWetlH/sM7bLtv UWzg== X-Gm-Message-State: APjAAAWsB/FWO1nbt1o+Tw7uPoygR6eb65FN1D5A8nlICFmt50MvjAmr vI0Olst3bHpZ/ZiewovWeKEfWX22lR8= X-Google-Smtp-Source: APXvYqyaAjbxLUYN31f0M8dB1Xu+acVGKJbWMabMayMpTv9uDhrqXq7gdgr3+Xrf6IIku8SnhVZ3hA== X-Received: by 2002:a2e:2201:: with SMTP id i1mr10050868lji.110.1575691307262; Fri, 06 Dec 2019 20:01:47 -0800 (PST) Received: from mail-lf1-f46.google.com (mail-lf1-f46.google.com. [209.85.167.46]) by smtp.gmail.com with ESMTPSA id j18sm7441357lfh.6.2019.12.06.20.01.46 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 06 Dec 2019 20:01:46 -0800 (PST) Received: by mail-lf1-f46.google.com with SMTP id m30so6769279lfp.8 for ; Fri, 06 Dec 2019 20:01:46 -0800 (PST) X-Received: by 2002:ac2:465e:: with SMTP id s30mr6736611lfo.134.1575691305722; Fri, 06 Dec 2019 20:01:45 -0800 (PST) MIME-Version: 1.0 References: <157558502272.10278.8718685637610645781.stgit@warthog.procyon.org.uk> <20191206135604.GB2734@twin.jikos.cz> In-Reply-To: From: Linus Torvalds Date: Fri, 6 Dec 2019 20:01:29 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 0/2] pipe: Fixes [ver #2] To: David Sterba , David Howells , Linus Torvalds , Eric Biggers , Al Viro , linux-fsdevel , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 6, 2019 at 7:50 PM Linus Torvalds wrote: > > I assume it's the added "do_wakeup = 0" (not the spinlock) that ends > up having some subtle issue. Ahh, and then later that is removed, but when it is removed it also remote the wakeup before the pipe_wait(). So whatever issue that commit introduces ends up remaining. I wonder if the extra wakeups ended up hiding some other bug. We do extra wakeups on the write side too, with a "FIXME! Is this really true?" comment.. Linus