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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 14AE9C4320A for ; Fri, 30 Jul 2021 19:24:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EA7D060F01 for ; Fri, 30 Jul 2021 19:24:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230461AbhG3TY0 (ORCPT ); Fri, 30 Jul 2021 15:24:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230402AbhG3TYZ (ORCPT ); Fri, 30 Jul 2021 15:24:25 -0400 Received: from mail-lf1-x133.google.com (mail-lf1-x133.google.com [IPv6:2a00:1450:4864:20::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8CC0C061765 for ; Fri, 30 Jul 2021 12:24:19 -0700 (PDT) Received: by mail-lf1-x133.google.com with SMTP id p38so5032232lfa.0 for ; Fri, 30 Jul 2021 12:24:19 -0700 (PDT) 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 :cc; bh=mlZRTu+F0o6A8qh5wibGN8Kxtu6GVrlOQ+jra2A0ypw=; b=VphtNkf0G/ZxdbSdJpJzgxkywMFcq1UHxJnjZdCDE57WkxcLiIrN61VNPYQac5bOpk hzseshWLh8ffqXoaL+BdguaYgNlzWPDe5sacat3uwFxH2Xb3YxRGk8hwNauNLDtrOr1p KCX50L4qjXUnogsRN6IM9EICxclKNh4O3UxrE= 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:cc; bh=mlZRTu+F0o6A8qh5wibGN8Kxtu6GVrlOQ+jra2A0ypw=; b=bNbEJEQ4or1YYibQ93gdrcuIzlM+WkvP3rEpo6ZzJGc3UO7LRRyFVpOaATd0E7VsqZ bos/SeY805Mm0BAryMlSser2LF8Lns6Mj0A+ttU5RUwdL1aVFdEHjcehHvv/mLFUeHAY y5JL50kNQSVrkHXXTHQUHFNUkgpjHk0yT5nvUqH8sekL+iVbZxU7rjDv8siyU85eRvqH WVllbxzExJDbDcSdVL3bCS7fzUpHxHNUlaVzb4H2zoZC/+bqSvY6MRi3VfPMKtoFGCFX MVU46l62aZXJ7m+cI6sP4EOoh0cRLI8KdHX25O6yHlEVWexnmN/Pjq4X6nZhcDZnBO5s GrIg== X-Gm-Message-State: AOAM531vCHR4CzPqObyiS0NILt2/OICRbmoOUY1ConEsv18WgixnRMhf w/7jT/BgdANux9RM+7IlEX0vI7OWH6GKPMkO X-Google-Smtp-Source: ABdhPJxmfBzX5LkcHP/Jcvuh/krqVC/splBcITtO2lVVwJ98X57LG7kNEeoeH4gAvdtVVPjcCIINoA== X-Received: by 2002:ac2:5979:: with SMTP id h25mr3004031lfp.393.1627673057268; Fri, 30 Jul 2021 12:24:17 -0700 (PDT) Received: from mail-lf1-f47.google.com (mail-lf1-f47.google.com. [209.85.167.47]) by smtp.gmail.com with ESMTPSA id t30sm218119lfg.289.2021.07.30.12.24.15 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 30 Jul 2021 12:24:15 -0700 (PDT) Received: by mail-lf1-f47.google.com with SMTP id r26so20003067lfp.5 for ; Fri, 30 Jul 2021 12:24:15 -0700 (PDT) X-Received: by 2002:a05:6512:2388:: with SMTP id c8mr2853330lfv.201.1627673054956; Fri, 30 Jul 2021 12:24:14 -0700 (PDT) MIME-Version: 1.0 References: <20210729222635.2937453-1-sspatil@android.com> <20210729222635.2937453-2-sspatil@android.com> In-Reply-To: From: Linus Torvalds Date: Fri, 30 Jul 2021 12:23:59 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 1/1] fs: pipe: wakeup readers everytime new data written is to pipe To: Sandeep Patil Cc: linux-fsdevel , Linux Kernel Mailing List , David Howells , Greg Kroah-Hartman , stable , Android Kernel Team Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 30, 2021 at 12:11 PM Sandeep Patil wrote: > > Yes, your patch fixes all apps on Android I can test that include this > library. Ok, thanks for checking. > fwiw, the library seems to have been fixed. However, I am not sure > how long it will be for all apps to take that update :(. I wonder if I could make the wakeup logic do this only for the epollet case. I'll have to think about it, but maybe I'll just apply that simple patch. I dislike the pointless wakeups, and as long as the only case I knew of was only a test of broken behavior, it was fine. But now that you've reported actual application breakage, this is in the "real regression" category, and so I'll fix it one way or the other. And on the other hand I also have a slight preference towards your patch simply because you did the work of finding this out, so you should get the credit. I'll mull it over a bit more, but whatever I'll do I'll do before rc4 and mark it for stable. Thanks for testing, Linus