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=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 97C81C2BA19 for ; Sun, 5 Apr 2020 22:52:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6805D20672 for ; Sun, 5 Apr 2020 22:52:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=anarazel.de header.i=@anarazel.de header.b="aWfcGa/g"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="DLHnqaRd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727889AbgDEWwn (ORCPT ); Sun, 5 Apr 2020 18:52:43 -0400 Received: from new3-smtp.messagingengine.com ([66.111.4.229]:51617 "EHLO new3-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727254AbgDEWwn (ORCPT ); Sun, 5 Apr 2020 18:52:43 -0400 Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailnew.nyi.internal (Postfix) with ESMTP id 66A9858013A; Sun, 5 Apr 2020 18:52:42 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute3.internal (MEProxy); Sun, 05 Apr 2020 18:52:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=anarazel.de; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm1; bh=euu86y6yACvCvstNFbv3DwBO9Kn QxP4jRh+eEX/Uz4E=; b=aWfcGa/g12RY6GgtiE4vbPeqndfFU5TauoaxI2sn/mk nSPdTiGGwqKZY5eH6mP0/5QnVVwdwJT91KjE8Yo0IiXVZKPvzwSvvxuRSLq8YaZs XcE9L7BSvZor3cZY1JEYNmy1I71P4ghowrUcuvJxMq4Dckhj6uHkRdSg0ZzkOJaf uM3YLFa4ZTDNyulM+BbWAOfTTUdN1oEbMeIwNHWmh0/7y4NPGesKQ7jutWt6POiX KU2Vwd6J6CVwXy1/IfGGRE6GcyWCGat9lp3810xCGBpRsj/I+DZjq3LBUR/P9gEl ufil6hnKfzU7gGfgjAHSzVqpFF6ylNsQusqXGRYBZFA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=euu86y 6yACvCvstNFbv3DwBO9KnQxP4jRh+eEX/Uz4E=; b=DLHnqaRdNucpqbnHm1V02h VvZajeUd3i21cHyA+Db+q5To2ahUXvySaDB14pwmjC6n6SN4J/h7uM4qhTVWnnt+ TtkUaFOVP+/9qPPXFNMdcqZPuFodmM5mcyR0VB+e8kDVPUndmWBDUMzF5b19gMCF YH4g3VBkFQphkpZvAKDDU650xCEbTJvpfEo7bDmmWAlMrGmy0BWY7YIbwXkZEZQ7 4y6kOk5oOpIs0LIEl2fX5apAjMQ2zEyykKmzB6D1nzTlE8kcrOQP2t5TvITsITW5 pGypOMF+cd9fetOY1v1UJmVJsvIBraTSlnh+QkJOjeWOrp7y1AhV6AaSaHSpQMNg == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduhedruddvgdduhecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpeffhffvuffkfhggtggujgesthdtredttddtvdenucfhrhhomheptehnughrvghs ucfhrhgvuhhnugcuoegrnhgurhgvshesrghnrghrrgiivghlrdguvgeqnecuffhomhgrih hnpehkvghrnhgvlhdrohhrghenucfkphepieejrdduiedtrddvudejrddvhedtnecuvehl uhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomheprghnughrvghsse grnhgrrhgriigvlhdruggv X-ME-Proxy: Received: from intern.anarazel.de (c-67-160-217-250.hsd1.ca.comcast.net [67.160.217.250]) by mail.messagingengine.com (Postfix) with ESMTPA id 5A2FC328005A; Sun, 5 Apr 2020 18:52:41 -0400 (EDT) Date: Sun, 5 Apr 2020 15:52:40 -0700 From: Andres Freund To: Linus Torvalds Cc: David Howells , Al Viro , dray@redhat.com, Karel Zak , Miklos Szeredi , Steven Whitehouse , jlayton@redhat.com, Ian Kent , Christian Brauner , keyrings@vger.kernel.org, linux-fsdevel , Linux Kernel Mailing List Subject: Re: [GIT PULL] Mount and superblock notifications Message-ID: <20200405225240.kofadjkmpigfzcfy@alap3.anarazel.de> References: <1445647.1585576702@warthog.procyon.org.uk> <1449543.1585579014@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 2020-04-04 14:13:03 -0700, Linus Torvalds wrote: > And it needs to be interesting and pressing enough that those people > actually at least do a working prototype on top of a patch-set that > hasn't made it into the kernel yet. > > Now, I realize that other projects won't _upstream_ their support > before the kernel has the infrastructure, so I'm not looking for > _that_ kind of "yeah, look, project XYZ already does this and Red Hat > ships it". No, I'm looking for those outside developers who say more > than "this is a pet peeve of mine with the existing interface". I want > to see some actual use - even if it's just in a development > environment - that shows that it's (a) sufficient and (b) actually > fixes problems. FWIW, postgres remains interested in using the per-superblock events. On 2020-03-30 15:36:54 +0100, David Howells wrote: > (2) Superblock notifications. > > This one is provided to allow systemd or the desktop to more easily > detect events such as I/O errors and EDQUOT/ENOSPC. This would be of > interest to Postgres: > > https://lore.kernel.org/linux-fsdevel/20200211005626.7yqjf5rbs3vbwagd@alap3.anarazel.de/ > > But could also be used to indicate to systemd when a superblock has > had its configuration changed. What prevents me from coming up with a prototype is that the error handling pieces aren't complete, as far as I can tell: On 2020-03-30 15:36:54 +0100, David Howells wrote: > (2) Superblock events, such as R/W<->R/O changes, quota overrun and I/O > errors (not complete yet). There's afaict no notify_sb_error() callers, making it hard for me to actually test anything. The important issue for us is I/O errors, but EDQUOT/ENOSPC could also be useful (but is not urgent). Greetings, Andres Freund