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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 6B289C43219 for ; Mon, 29 Apr 2019 16:59:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3B3AA2087B for ; Mon, 29 Apr 2019 16:59:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728861AbfD2Q72 (ORCPT ); Mon, 29 Apr 2019 12:59:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46278 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728695AbfD2Q72 (ORCPT ); Mon, 29 Apr 2019 12:59:28 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 214813091784; Mon, 29 Apr 2019 16:59:28 +0000 (UTC) Received: from x1.home (ovpn-116-122.phx2.redhat.com [10.3.116.122]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4406B1001E63; Mon, 29 Apr 2019 16:59:27 +0000 (UTC) Date: Mon, 29 Apr 2019 10:59:26 -0600 From: Alex Williamson To: Sinan Kaya Cc: Bjorn Helgaas , mr.nuke.me@gmail.com, linux-pci@vger.kernel.org, austin_bolen@dell.com, alex_gagniuc@dellteam.com, keith.busch@intel.com, Shyam_Iyer@Dell.com, lukas@wunner.de, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI: Add link_change error handler and vfio-pci user Message-ID: <20190429105926.209d17d3@x1.home> In-Reply-To: <76169da9-36cd-6754-41e7-47c8ef668648@kernel.org> References: <155605909349.3575.13433421148215616375.stgit@gimli.home> <20190424175758.GC244134@google.com> <20190429085104.728aee75@x1.home> <76169da9-36cd-6754-41e7-47c8ef668648@kernel.org> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Mon, 29 Apr 2019 16:59:28 +0000 (UTC) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, 29 Apr 2019 09:45:28 -0700 Sinan Kaya wrote: > On 4/29/2019 10:51 AM, Alex Williamson wrote: > > So where do we go from here? I agree that dmesg is not necessarily a > > great choice for these sorts of events and if they went somewhere else, > > maybe I wouldn't have the same concerns about them generating user > > confusion or contributing to DoS vectors from userspace drivers. As it > > is though, we have known cases where benign events generate confusing > > logging messages, which seems like a regression. Drivers didn't ask > > for a link_change handler, but nor did they ask that the link state to > > their device be monitored so closely. Maybe this not only needs some > > sort of change to the logging mechanism, but also an opt-in by the > > driver if they don't expect runtime link changes. Thanks, > > Is there anyway to detect autonomous hardware management support and > not report link state changes in that situation? > > I thought there were some capability bits for these. Not that we can find, this doesn't trigger the separate autonomous bandwidth notification interrupt. Thanks, Alex