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=-3.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_NEOMUTT 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 D2946C28EB4 for ; Thu, 6 Jun 2019 14:34:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AC9D620673 for ; Thu, 6 Jun 2019 14:34:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=brauner.io header.i=@brauner.io header.b="MBprUpp1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728911AbfFFOed (ORCPT ); Thu, 6 Jun 2019 10:34:33 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:43160 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728846AbfFFOec (ORCPT ); Thu, 6 Jun 2019 10:34:32 -0400 Received: by mail-pf1-f193.google.com with SMTP id i189so1609450pfg.10 for ; Thu, 06 Jun 2019 07:34:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=brauner.io; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=uliRl25tF2O1ExnxNI5OeemcUVuWp/hZHc1pbbwUvtw=; b=MBprUpp1e5VKUe+T74LmM6i0Ek4WwUD8SNxviqye9qRCXjeQD1AN2cQwMjMeLOJAFU gJe75uGQWbYYHmyw2x5BvtU5ncrcFbkHTESEAOA1dzwscKIbkZKdQNpmnqFhKnBmc3zQ EGOBnm10P7Akkmw3M7Phxq/g7hqCRhz0eQ+B4qicHZCKeanltJAA1IX5vvqIsNB6EU1V ffagFv4poPie3Oi6fc6m4FO/7bfLmtOyca95WSoReHg1f/VgYW1TP1sk+8d73DWcuplv eVzc1ya3v/2UecxqoJ+Sq8Lb0zxNK7qHeBb63mjflhEmiQno3Q0gxTPT2+o1bJzLxiLZ ZnSw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=uliRl25tF2O1ExnxNI5OeemcUVuWp/hZHc1pbbwUvtw=; b=BbI1qrF8il5VO6HTiikI1YGqyJtW0N4qSufMd/19801SvVIi5pS85iVIrWAUR2xTs9 UaVUCTMGaGLOjAvRR3H82RmHfaF37qjuztczCBp1nCuNmk0kRFkv0VGW8gEIjCMUCkN4 37uRbQyXazrPErL0y0J4+Pz6Cxz15ORh4P+dKP7j0v/RDooVTvlf6VtxvLks0fqzuoS4 Km/JaEMQ67AkgmW6xRxNFe5Kah0FFMPAa0KpD478FFt2r9Sq+2NZMcBlR0JYkxqxKiTp K6Tm9RhExQX5rdZChamv12l5LvVUtD/P5totuRkvGhD91bcthSaMFHWO4ZkI+luhx8Xe +9iQ== X-Gm-Message-State: APjAAAVbB2qG7Ej0Vdu4/ACQjfGcD/EhsSvcXQr7sE71jgOxOD+ardAv R70IgwchupMI4vmocxg5SwXU2Q== X-Google-Smtp-Source: APXvYqzIL8wsldD4bies6ebY7rZKopPTvKboOK8nOCrGaFcXy8cI3glqwYs+CwKGEY8yNiE0aUv+Rw== X-Received: by 2002:a63:dd05:: with SMTP id t5mr3525537pgg.229.1559831671810; Thu, 06 Jun 2019 07:34:31 -0700 (PDT) Received: from brauner.io ([172.56.30.175]) by smtp.gmail.com with ESMTPSA id l7sm2552259pfl.9.2019.06.06.07.34.25 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Thu, 06 Jun 2019 07:34:31 -0700 (PDT) Date: Thu, 6 Jun 2019 16:34:21 +0200 From: Christian Brauner To: David Howells Cc: viro@zeniv.linux.org.uk, Greg Kroah-Hartman , Casey Schaufler , linux-usb@vger.kernel.org, raven@themaw.net, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-block@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC][PATCH 00/10] Mount, FS, Block and Keyrings notifications [ver #3] Message-ID: <20190606143420.hxjximmhigpa2nti@brauner.io> References: <155981411940.17513.7137844619951358374.stgit@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <155981411940.17513.7137844619951358374.stgit@warthog.procyon.org.uk> User-Agent: NeoMutt/20180716 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Thu, Jun 06, 2019 at 10:41:59AM +0100, David Howells wrote: > > Hi Al, > > Here's a set of patches to add a general variable-length notification queue > concept and to add sources of events for: > > (1) Mount topology events, such as mounting, unmounting, mount expiry, > mount reconfiguration. > > (2) Superblock events, such as R/W<->R/O changes, quota overrun and I/O > errors (not complete yet). > > (3) Key/keyring events, such as creating, linking and removal of keys. > > (4) General device events (single common queue) including: > > - Block layer events, such as device errors > > - USB subsystem events, such as device/bus attach/remove, device > reset, device errors. > > One of the reasons for this is so that we can remove the issue of processes > having to repeatedly and regularly scan /proc/mounts, which has proven to > be a system performance problem. To further aid this, the fsinfo() syscall > on which this patch series depends, provides a way to access superblock and > mount information in binary form without the need to parse /proc/mounts. > > > LSM support is included, but controversial: Apart from the LSM/security controversy here the general direction of this patchset is pretty well received it seems. Imho, having a notification mechanism like this is a very good thing for userspace. So would be great if there'd be a consensus on the LSM bits. Christian