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=-17.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 6E491C6369E for ; Wed, 2 Dec 2020 21:59:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19B1C2222E for ; Wed, 2 Dec 2020 21:59:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726462AbgLBV7n (ORCPT ); Wed, 2 Dec 2020 16:59:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56342 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726056AbgLBV7n (ORCPT ); Wed, 2 Dec 2020 16:59:43 -0500 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 48F03C0613D6; Wed, 2 Dec 2020 13:59:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender :Reply-To:Content-ID:Content-Description; bh=kb88isD6UQQ4pziP8SfHAEy2NFf6PJ4pThmNMqkixS8=; b=TZ2iztmnYBglqeDgARHeQtuI6D w/4ool4sdNQUoWgs40IzXH3FWlzlME6PYj49zBlJjKcLxncikwnCK2K47Wgnq20V0gNtlPUuXXPXu HRV7v9vJsoXGBAiLtXTP8zN5m4Zmq74k8a4Hphk9gt82isbMNjBVvIx4BQAfyDVtm6RPjaTxsifGT PDBUqLrqyF0eRLaH9glhquxGL7b1msYMlyGKTE83ZYHq4lNJSF90BmjcaDHN6rZ0rCqcpjc2YB/5k xUP5JMr8s+eX/S0MsLTHkVktRhWvC1zwA07W/Un9HDKhkipVWY9e5A6OLmIyjQcnjwtLDVG0SjCw4 VoEqQc7w==; Received: from [2601:1c0:6280:3f0::1494] by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kka9K-0002lr-W9; Wed, 02 Dec 2020 21:58:59 +0000 Subject: Re: [PATCH v2 2/2] x86: make Hyper-V support optional To: "Enrico Weigelt, metux IT consult" , linux-kernel@vger.kernel.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, dmitry.torokhov@gmail.com, derek.kiernan@xilinx.com, dragan.cvetic@xilinx.com, richardcochran@gmail.com, linux-hyperv@vger.kernel.org, linux-input@vger.kernel.org, netdev@vger.kernel.org References: <20201202211949.17730-1-info@metux.net> <20201202211949.17730-2-info@metux.net> From: Randy Dunlap Message-ID: Date: Wed, 2 Dec 2020 13:58:52 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.4.0 MIME-Version: 1.0 In-Reply-To: <20201202211949.17730-2-info@metux.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On 12/2/20 1:19 PM, Enrico Weigelt, metux IT consult wrote: > Make it possible to opt-out from Hyper-V support, for minimized kernels > that never will by run under Hyper-V. (eg. high-density virtualization > or embedded systems) > > Average distro kernel will leave it on, therefore default to y. > > Signed-off-by: Enrico Weigelt > --- > arch/x86/Kconfig | 11 +++++++++++ > arch/x86/kernel/cpu/Makefile | 4 ++-- > arch/x86/kernel/cpu/hypervisor.c | 2 ++ > drivers/hv/Kconfig | 2 +- > 4 files changed, 16 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index eff12460cb3c..57d20591d6ee 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -812,6 +812,17 @@ config VMWARE_GUEST > density virtualization or embedded systems running (para)virtualized > workloads. > > +config HYPERV_GUEST > + bool "Hyper-V Guest support" > + default y > + help > + This option enables several optimizations for running under the > + Hyper-V hypervisor. > + > + Disabling it saves a few kb, for stripped down kernels eg. in high kB, e.g. > + density virtualization or embedded systems running (para)virtualized > + workloads. > + > config KVM_GUEST > bool "KVM Guest support (including kvmclock)" > depends on PARAVIRT -- ~Randy