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 31041CD11BF for ; Tue, 19 Mar 2024 15:31:47 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rmbQO-00089s-0i; Tue, 19 Mar 2024 11:30:50 -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 1rmbQL-00089Q-UC for qemu-devel@nongnu.org; Tue, 19 Mar 2024 11:30:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rmbQF-0002WH-UX for qemu-devel@nongnu.org; Tue, 19 Mar 2024 11:30:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1710862238; h=from:from:reply-to: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=37GFYLI5MyQqq4540bATPhxNX5uMFiPaTnTj87Z/d5c=; b=OzVwdv9wXsB/xaimThbEWOA5z2lAnashbzljBREXj64VCcdi4WpAkmHhH+ZIunu/2Lq29E lLRwoDn7cHaSO+aOLymgpDTXymG1vNg6vuRCdGDyvemWfqWmDCkrhR511uQQXIquzsr8DQ cskXegArJKlfJl+zbYKmruz4tkT+juI= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-629-kU30rjpWMg214CtLgs35JA-1; Tue, 19 Mar 2024 11:30:35 -0400 X-MC-Unique: kU30rjpWMg214CtLgs35JA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id 583D2101CC6F; Tue, 19 Mar 2024 15:30:34 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.88]) by smtp.corp.redhat.com (Postfix) with ESMTPS id BE9B740C6DAD; Tue, 19 Mar 2024 15:30:32 +0000 (UTC) Date: Tue, 19 Mar 2024 15:30:09 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Peter Maydell Cc: Eric Auger , Shaoqin Huang , qemu-arm@nongnu.org, Sebastian Ott , Paolo Bonzini , qemu-devel@nongnu.org, kvm@vger.kernel.org Subject: Re: [PATCH v7] arm/kvm: Enable support for KVM_ARM_VCPU_PMU_V3_FILTER Message-ID: References: <20240221063431.76992-1-shahuang@redhat.com> <0f8380d9-bdca-47b2-93d9-ee8f6382e7f1@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/2.2.12 (2023-09-09) X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.2 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.422, 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, Mar 19, 2024 at 03:00:40PM +0000, Peter Maydell wrote: > On Tue, 19 Mar 2024 at 14:57, Eric Auger wrote: > > > > Hi Peter, > > > > On 2/29/24 12:00, Peter Maydell wrote: > > > > > > It doesn't appear because the list of properties that we advertise > > > via query-cpu-model-expansion is set in the cpu_model_advertised_features[] > > > array in target/arm/arm-qmp-cmds.c, and this patch doesn't add > > > 'kvm-pmu-filter' to it. But you have a good point about all the > > > others being bool properties: I don't know enough about that > > > mechanism to know if simply adding this to the list is right. > > > > > > This does raise a more general question: do we need to advertise > > > the existence of this property to libvirt via QMP? Eric, Sebastian: > > > do you know ? > > sorry I missed this question. yes I think it is sensible to expose that > > option to libvirt. There is no good default value to be set at qemu > > level so to me it really depends on the upper stack to choose the > > correct value (depending on the sensitiveness of the data that justified > > the kernel uapi). > > In that case we should definitely have a mechanism for libvirt > to be able to say "does this QEMU (and this CPU) implement > this property?". Unfortunately my QMP/libvirt expertise is > too low to be able to suggest what that mechanism should be... Libvirt uses 'qom-list' on '/machine/unattached/device[0]' to identify CPU properties. If 'kvm-pmu-filter' appears with that, then detection will be fine. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|