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 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 6DD60D339A2 for ; Mon, 28 Oct 2024 16:37:54 +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:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Subject:Cc:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=u0c90wdXQNTwAkNRBquwxQ7vtlBQRTY/j+jjrbZTlBA=; b=YX7snElEegR6PRnoALnGGMRsVW 5dZbhjPVICZP3+lKkIZLhEs8PfG9IJEOwibV4KLF2HgF1DzMwO4DnOdcKJvAqvtJeO5LSwQAtvaj6 aDJMAFWNontw4px1BmkY1oVzu9+VhxO8fl8wEL63JmnUwVihvylwEg6BSwQppGIBlXvF/gQG7Q/xJ Qhs9zXZmjtqIV3GrkiBZRCjov7RV9NQ+eIJQR0mE+yFDf1DAeNNY5bTtj5zvHAb18FW6Hi2XdYAFg DMi9sw190Z35zYw6i1Gckud3N7QlfOGCecEByswdj/9HGjWBgmV/MRZwlg8p0zYbBmp7RNuvunLdG EStiB1Ug==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t5SkR-0000000BVuN-3vrA; Mon, 28 Oct 2024 16:37:43 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t5SMW-0000000BS2x-08AN for linux-arm-kernel@lists.infradead.org; Mon, 28 Oct 2024 16:13:01 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 33E935C5D58; Mon, 28 Oct 2024 16:12:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC1B6C4CEC3; Mon, 28 Oct 2024 16:12:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730131979; bh=xuzSVIC+24hcvUH3Uu6IJyxDoI8NF9z/u0YhE9kqbOY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=C0q+lkSKR1cXdmfA70QriKxNHoGAVcH+ZKCc+Zox4ygDHb48qTdn8VuHT2A4+o5V2 zoili6j4ZeZdYddsbvCBmzv4/WQgpSj7kTlw06ahaK4hCP3zTRP9o3R85+DvpU2GYF JOfOD4cd4nqkmkIlo1feNr7WS5I7Lq9w9Ag0huIfm0H86flbsmELoeR1CWqpKwnAA6 NYQH1pJbxeuWuW0ou07d6MW7v+ovxkDt0VgRA/OeSEyVzpisDjPRrKkn0IRURMLEiE huG9vkW7i5jsybC0co+F32KJLuGZov4R0mWfhQFuXfe18nE4zlmADox5tRHMwhBpHw r+wobvKfES9+g== Date: Mon, 28 Oct 2024 09:12:56 -0700 From: Jakub Kicinski To: David Woodhouse 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 Subject: Re: [PATCH net-next v7] ptp: Add support for the AMZNC10C 'vmclock' device Message-ID: <20241028091256.1b0752b4@kernel.org> In-Reply-To: References: <78969a39b51ec00e85551b752767be65f6794b46.camel@infradead.org> <20241009173253.5eb545db@kernel.org> <20241014131238.405c1e58@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241028_091300_147336_8B98B4D9 X-CRM114-Status: GOOD ( 17.62 ) 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 On Sat, 19 Oct 2024 18:49:24 +0100 David Woodhouse wrote: > > Yes please and thank you! We gotta straighten it out before > > the merge window. > > Hm, as I (finally) come to do that, I realise that many of the others > defined in drivers/ptp/Kconfig are also 'default y'. Which is only > really 'default PTP_1588_CLOCK' in practice since they all depend on > that. AFAICT nothing defaulted to enabled since 2017, so I'd chalk it up to us getting better at catching mistakes over time. > Most importantly, PTP_1588_CLOCK_KVM is 'default y'. And that one is > fundamentally broken (at least in the presence of live migration if > guests care about their clock suddenly being wrong) which is why it's > being superseded by the new VMCLOCK thing. We absolutely don't want to > leave the _KVM one enabled by default and not its _VMCLOCK replacement. You can default to .._CLOCK_KVM, and provide the explanation in the commit message and Kconfig help. Or if you feel strongly even make CLOCK_KVM depend on the new one? > Please advise... I suspect the best answer is to leave it as it is? I'd really rather not. Linus has complained to us about Kconfig symbols appearing / getting enabled by default multiple times in the past. Sorry for the delay, vacation time.