From patchwork Sat Nov 2 21:52:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Woodhouse X-Patchwork-Id: 13860248 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 58A78E67814 for ; Sat, 2 Nov 2024 21:54:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:MIME-Version:Content-Type: Date:Cc:To:From:Subject:Message-ID:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=O+qYEcV6Zo/oc9EEp/w/DPcytGgJzkO9IjpgAtYj+O0=; b=VAQawNGIDS7HZUmjgPePENMh1w 2xbDZIHlOVdB0lRoqX1otEQ2BmGi676EjbQYgVRcdlHfNjh86uIThXxKV73+GeVd3pqXvM1GSAqEU LpMY4WRWcY8c6gQgFYbMNhOocBfqOuXwGMUZhwE9UJRNtqc7zBr+vqqx7J7aiC7J0ulDjwikOG2dj CluNdTQCoR3MmehtUaFdfyRqBKXmB3ILFLn0ci1qAAlwsakoUODuZdi/OwsY68jPYNDU1Qpib+tk+ vZDMw15lQVhxEXuWLkXs2DdE30yhLE462iBd04n0i+vKXSDfTvna5FC0ApemW7c7aX1UXZr7Hn3Rd ruOtmGAQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t7M4U-0000000ATQI-2Blx; Sat, 02 Nov 2024 21:54:14 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t7M2p-0000000ATEv-4157 for linux-arm-kernel@bombadil.infradead.org; Sat, 02 Nov 2024 21:52:32 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=MIME-Version:Content-Type:Date:Cc:To: From:Subject:Message-ID:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:In-Reply-To:References; bh=O+qYEcV6Zo/oc9EEp/w/DPcytGgJzkO9IjpgAtYj+O0=; b=MGXJoxd8P3hpfIACVYMPLRB/BZ KBr1IR3xqoppaJ4XqC6y2PDPE8ZkH9XAFO/t70f/9jIghRLmuzY97PdbisawsnzrfJiBzFAbvhlNw 9oRT2C4JaZKrxaVbbu8ZKC/V6ZbANkPuluUGIVOtsIkcksLXapfECTDQFpKKVJD9COS0M3A2a7jVa zRiF4/dT6gWGXLu+8q3ph4OaxHklFGEini5KI1boyaUsEw7DeFKu2fjGNY7ZfB6xAysTHMSF3vBoK edwT9if9npd7KYn6to6slvTobNDkT7wA3j4H0LeOnCSO31yin/2glmrI8uXQxWsxKJyT+e0+AyyJh zR0JmVRg==; Received: from [52.94.133.142] (helo=edge-m2-r1-128.e-lax51.amazon.com) by casper.infradead.org with esmtpsa (Exim 4.98 #2 (Red Hat Linux)) id 1t7M2g-0000000HAoP-31ix; Sat, 02 Nov 2024 21:52:24 +0000 Message-ID: <89955b74d225129d6e3d79b53aa8d81d1b50560f.camel@infradead.org> Subject: [PATCH net-next] ptp: Remove 'default y' for VMCLOCK PTP device From: David Woodhouse To: Jakub Kicinski Cc: Richard Cochran , Peter Hilber , linux-kernel@vger.kernel.org, virtualization@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-rtc@vger.kernel.org, "Ridoux, Julien" , virtio-dev@lists.linux.dev, "Luu, Ryan" , "Chashper, David" , "Mohamed Abuelfotoh, Hazem" , Paolo Abeni , "Christopher S . Hall" , Jason Wang , John Stultz , "Michael S . Tsirkin" , netdev@vger.kernel.org, Stephen Boyd , Thomas Gleixner , Xuan Zhuo , Marc Zyngier , Mark Rutland , Daniel Lezcano , Alessandro Zummo , Alexandre Belloni , qemu-devel , Simon Horman Date: Sat, 02 Nov 2024 16:52:17 -0500 User-Agent: Evolution 3.44.4-0ubuntu2 MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: David Woodhouse The VMCLOCK device gives support for accurate timekeeping even across live migration, unlike the KVM PTP clock. To help ensure that users can always use ptp_vmclock where it's available in preference to ptp_kvm, set it to 'default PTP_1588_CLOCK_VMCLOCK' instead of 'default y'. Signed-off-by: David Woodhouse --- drivers/ptp/Kconfig | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig index e98c9767e0ef..ed087ae75f0e 100644 --- a/drivers/ptp/Kconfig +++ b/drivers/ptp/Kconfig @@ -135,12 +135,16 @@ config PTP_1588_CLOCK_VMCLOCK tristate "Virtual machine PTP clock" depends on X86_TSC || ARM_ARCH_TIMER depends on PTP_1588_CLOCK && ACPI && ARCH_SUPPORTS_INT128 - default y + default PTP_1588_CLOCK_KVM help This driver adds support for using a virtual precision clock advertised by the hypervisor. This clock is only useful in virtual machines where such a device is present. + Unlike the KVM virtual PTP clock, the VMCLOCK device offers support + for reliable timekeeping even across live migration. So this driver + is enabled by default whenever the KVM PTP clock is. + To compile this driver as a module, choose M here: the module will be called ptp_vmclock.