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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 680E2C87FC9 for ; Tue, 29 Jul 2025 16:22:04 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ugn4d-0007T1-6I; Tue, 29 Jul 2025 12:21:07 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ugmm7-0001gN-FI for qemu-devel@nongnu.org; Tue, 29 Jul 2025 12:02:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ugmm1-0007lO-Ti for qemu-devel@nongnu.org; Tue, 29 Jul 2025 12:01:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1753804892; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SGYv72RxjZ33ADQVQ3rOtxtJu0wJd3kwSPw8DblHG1Q=; b=gqwYZb0hdBCQWiHF0R7AeUTfTlOt24b5TxU/guaVRzflNInYGN6tqlrKZox4g2W7lO0rTS OFqfNLgV6JxDpubxkq4MCoKEmCtVV9sLH06tLbGiXWywA9dpQSIvUtARfcJbBznwnNkvIu ayRinhd1kYOLv97SqsHtgZAkqLMft9U= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-520-VyBVxoNCOL-I0sX1TfgxzQ-1; Tue, 29 Jul 2025 12:01:30 -0400 X-MC-Unique: VyBVxoNCOL-I0sX1TfgxzQ-1 X-Mimecast-MFC-AGG-ID: VyBVxoNCOL-I0sX1TfgxzQ_1753804889 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1BAC618007E1 for ; Tue, 29 Jul 2025 16:01:29 +0000 (UTC) Received: from localhost (unknown [10.44.34.3]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 448331955F21; Tue, 29 Jul 2025 16:01:28 +0000 (UTC) From: Cornelia Huck To: =?utf-8?Q?Daniel_P=2E_Berrang=C3=A9?= Cc: Andrea Bolognani , Paolo Bonzini , "Michael S. Tsirkin" , qemu-devel@nongnu.org Subject: Re: [PATCH 2/2] watchdog: generic name for i6300esb In-Reply-To: Organization: "Red Hat GmbH, Sitz: Werner-von-Siemens-Ring 12, D-85630 Grasbrunn, Handelsregister: Amtsgericht =?utf-8?Q?M=C3=BCnchen=2C?= HRB 153243, =?utf-8?Q?Gesch=C3=A4ftsf=C3=BChrer=3A?= Ryan Barnhart, Charles Cachera, Avril Crosse O'Flaherty" References: <20250610143259.1056400-1-cohuck@redhat.com> <20250610143259.1056400-3-cohuck@redhat.com> <877c09792e.fsf@redhat.com> <874iva7so9.fsf@redhat.com> User-Agent: Notmuch/0.38.3 (https://notmuchmail.org) Date: Tue, 29 Jul 2025 18:01:25 +0200 Message-ID: <87tt2v3s16.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.133.124; envelope-from=cohuck@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Thu, Jul 17 2025, Daniel P. Berrang=C3=A9 wrote: > On Thu, Jul 17, 2025 at 05:17:42PM +0200, Cornelia Huck wrote: >> On Tue, Jul 15 2025, Daniel P. Berrang=C3=A9 wrote: >>=20 >> > On Tue, Jul 15, 2025 at 09:16:24AM -0700, Andrea Bolognani wrote: >> >> You can point them to documentation over and over again, or you can >> >> work to prevent the confusion/annoyance from showing up in the first >> >> place. Which of the two approaches is a better use of anyone's time >> >> is up for debate. >> >>=20 >> >> I for one am grateful that someone put the time in all those years >> >> ago and, as a result, PCI and USB controllers don't suffer from the >> >> problem today. Ultimately it's up to Connie though. >> > >> > The PCI/USB controller situation is not the same tradeoff though. >> > Those guest kernel drivers will identify and attach to these two >> > controllers regardless of their PCI vendor/product, via the PCI >> > class property. In that case changing the PCI ID and other device >> > metadata in QEMU is cheap as it has no negative impact on guest OS >> > driver compibility. >> > >> > In the case of 6300ESB though the guest driver is tied directly to >> > the currently used PCI device product/vendor ID. >> > >> > If we change this then we have actually created new functional >> > problems with guest/QEMU compatibility, in order to placate a >> > non-functional problem. That is not a good thing. >>=20 >> I don't think the suggestion was to disable the existing driver on >> non-Intel setups, but to add a more generic one. Still, more work to get >> this actually propagated into guests than doing the change in >> QEMU. Before I start down that route, I'd like to know whether the issue >> is actually big enough to make investing time there worth it. > > If we're a mmgmt app provisioning a guest, we have to choose what > watchdog to create - either the old one which works everywhere > that currently has a driver, or the new one will will work in > far fewer places. We'll have to wire up guest OS info about > watchdogs into osinfo, and then wire up all the mgmt apps to > query this and take action based off it. All possible, but it > still feels like a huge waste of time to me. The fact that the device is something emulated and not the Intel hardware device is actually visible to the guest: 00:02.0 System peripheral: Intel Corporation 6300ESB Watchdog Timer Subsystem: Red Hat, Inc. QEMU Virtual Machine Flags: fast devsel Memory at 10804000 (32-bit, non-prefetchable) [size=3D16] Kernel driver in use: i6300ESB timer Kernel modules: i6300esb (lspci -v so unfortunately not immediately obvious, but still) AFAIK the BSDs do not have a driver for this device at the moment -- and given what turns up when searching for i6300ESB, someone implementing a driver is far more likely to pick the exising PCI ID. Windows would also need some dance according to Yan's mail, for unclear benefits. On the whole, I think this is not really worth the hassle, we can simply keep this device as-is.