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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 27F0CC10F00 for ; Thu, 28 Feb 2019 08:10:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E937A2184A for ; Thu, 28 Feb 2019 08:10:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=szeredi.hu header.i=@szeredi.hu header.b="KuDdJDxZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731320AbfB1IK1 (ORCPT ); Thu, 28 Feb 2019 03:10:27 -0500 Received: from mail-it1-f194.google.com ([209.85.166.194]:53301 "EHLO mail-it1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725973AbfB1IK1 (ORCPT ); Thu, 28 Feb 2019 03:10:27 -0500 Received: by mail-it1-f194.google.com with SMTP id v2so13436079ith.3 for ; Thu, 28 Feb 2019 00:10:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=szeredi.hu; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=SqfH+kuUOMTrF6vj1gs8eqqPsjdoIHEXeiT0WqnxlkU=; b=KuDdJDxZCF/Qa71uGD4yZtTFb3ri7LuWP3hZQhOFBXTVgOXBxacDHQhJ86hIYdtALi WUfH4UOR/D+wMHSqkGPiZdT4OkkB8zHcVQI38lQKSiX40GtFkYq1am/Sn7McsAryb1e3 kAM3k/Zys30XbOGiF8Qze1QPSChq0VpquexHw= 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=SqfH+kuUOMTrF6vj1gs8eqqPsjdoIHEXeiT0WqnxlkU=; b=TwfO+kzdNPsWifRCTLyjFcPo0nYgmDMz7EKw/XrYB4Iv92Bv7p5iuWBdmmUbfyBzi2 dt7EX3kCyuKRzilS5aLu47XO/JK8ivze/oaWu0Q18O1GPuHzf3fRkyXJDJg4Vt4zZ6D7 bwQK+6XfvZhqpv98rwuh1YUBc88Uz0H5JSFl2yHSyqPSowX4g92qQhAdRsOPdS6tRKdn i4g/o7Ys36M2xfQPAyJ/7jGKNuIK1pDO68xayzUcYI0boEsOcbFPQ7ejORYbAC844KK/ QqjhTdaRHgiiHXXaQwyLkuwXn0VLTOv3ewPOTCH5kY1c6tJ55o1BFjBdLOJtdaLgZtRa 7j3Q== X-Gm-Message-State: APjAAAV5IoWV9m0Zxo82OO5fWbuZ5Cj0ax5hcP/VWqhZyHiTERSAKxJu IfMyeDiNWz3ktShI4NXy2qgeirynbY9y4qAG8sD/oTWD X-Google-Smtp-Source: APXvYqzrT59h3NjDXldmPTIVtTmn4HyU/8C+FQ0Aem8epVaUR4pOnFp2KIZx0PiKRtE3cIqwnW+nRL7BBgfr8zi5YLo= X-Received: by 2002:a24:3d0f:: with SMTP id n15mr2222404itn.1.1551341426792; Thu, 28 Feb 2019 00:10:26 -0800 (PST) MIME-Version: 1.0 References: <20190219094147.32734-1-kirr@nexedi.com> <20190227200155.GA14682@deco.navytux.spb.ru> <20190227203903.GA2798@deco.navytux.spb.ru> In-Reply-To: <20190227203903.GA2798@deco.navytux.spb.ru> From: Miklos Szeredi Date: Thu, 28 Feb 2019 09:10:15 +0100 Message-ID: Subject: Re: [RESEND, PATCH v2] fuse: Don't drop NOTIFY_REPLY if we promised it To: Kirill Smelkov Cc: Miklos Szeredi , linux-fsdevel@vger.kernel.org, fuse-devel , Han-Wen Nienhuys , Jakob Unterwurzacher , stable Content-Type: text/plain; charset="UTF-8" Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Wed, Feb 27, 2019 at 9:39 PM Kirill Smelkov wrote: > I more or less agree with this statement. However can we please make the > breakage to be explicitly visible with an error instead of exhibiting it > via harder to debug stucks/deadlocks? For example sys_read < max_write > -> error instead of getting stuck. And if notify_retrieve requests > buffer larger than max_write -> error or cut to max_write, but don't > return OK when we know we will never send what was requested to > filesystem even if it uses max_write sized reads. What is the point of > breaking in hard to diagnose way when we can make the breakage showing > itself explicitly? Would a patch for such behaviour accepted? Sure, if it's only adds a couple of lines. Adding more than say ten lines for such a non-bug fix is definitely excessive. Thanks, Miklos