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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 39463C433ED for ; Tue, 20 Apr 2021 17:37:14 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 9405C613C2 for ; Tue, 20 Apr 2021 17:37:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9405C613C2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:47588 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lYuJE-0008RP-9E for qemu-devel@archiver.kernel.org; Tue, 20 Apr 2021 13:37:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52608) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lYuI0-0007uD-S6 for qemu-devel@nongnu.org; Tue, 20 Apr 2021 13:35:56 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:36511) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lYuHy-0003wU-H7 for qemu-devel@nongnu.org; Tue, 20 Apr 2021 13:35:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1618940153; 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: in-reply-to:in-reply-to:references:references; bh=yMO+NtGLl2GYCJQByVvTGyfvxQlBhjABSJeTi9+Pd5c=; b=JjSHSGzQ/ZFboo8x74zfmcR/F0CwHrUOw4XpCtY/eC4ZBnbXGYYRksuVuCu21Mc7gGnfjb bruaOHn7NEm3NrfACpJCeqeZef/vU4Fz41YK/NqHlK8J32YkyN7EqKywWwsAD8H8UrrJis A8zsp098UyXrmnRJlRGQTSkyOCwmi54= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-453-fLs30hu7MFqzwKHYtx2pjQ-1; Tue, 20 Apr 2021 13:35:49 -0400 X-MC-Unique: fLs30hu7MFqzwKHYtx2pjQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A2E861020C31; Tue, 20 Apr 2021 17:35:48 +0000 (UTC) Received: from localhost (ovpn-118-208.rdu2.redhat.com [10.10.118.208]) by smtp.corp.redhat.com (Postfix) with ESMTP id 61C495D9DC; Tue, 20 Apr 2021 17:35:42 +0000 (UTC) Date: Tue, 20 Apr 2021 13:35:41 -0400 From: Eduardo Habkost To: "Dr. David Alan Gilbert" Subject: Re: [PATCH 0/2] i386: Fix interrupt based Async PF enablement Message-ID: <20210420173541.24kxarhw75h2rqxa@habkost.net> References: <20210401151957.408028-1-vkuznets@redhat.com> <87sg43d4gk.fsf@vitty.brq.redhat.com> <091dec53-cc0c-04ca-154a-3cfab6475705@redhat.com> MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=ehabkost@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Received-SPF: pass client-ip=216.205.24.124; envelope-from=ehabkost@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 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_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Vitaly Kuznetsov , Richard Henderson , qemu-devel@nongnu.org, "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, Apr 15, 2021 at 08:14:30PM +0100, Dr. David Alan Gilbert wrote: > * Paolo Bonzini (pbonzini@redhat.com) wrote: > > On 06/04/21 13:42, Vitaly Kuznetsov wrote: > > > older machine types are still available (I disable it for <= 5.1 but we > > > can consider disabling it for 5.2 too). The feature is upstream since > > > Linux 5.8, I know that QEMU supports much older kernels but this doesn't > > > probably mean that we can't enable new KVM PV features unless all > > > supported kernels have it, we'd have to wait many years otherwise. > > > > Yes, this is a known problem in fact. :( In 6.0 we even support RHEL 7, > > though that will go away in 6.1. > > > > We should take the occasion of dropping RHEL7 to be clearer about which > > kernels are supported. > > It would be nice to be able to define sets of KVM functonality that we > can either start given machine types with, or provide a separate switch > to limit kvm functionality back to some defined point. We do trip over > the same things pretty regularly when accidentally turning on new > features. The same idea can apply to the hyperv=on stuff Vitaly is working on. Maybe we should consider making a generic version of the s390x FeatGroup code, use it to define convenient sets of KVM and hyperv features. -- Eduardo