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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 36AC1C4338F for ; Mon, 16 Aug 2021 21:07:56 +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 B0C1660F11 for ; Mon, 16 Aug 2021 21:07:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org B0C1660F11 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:56384 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mFjpq-0007sJ-TV for qemu-devel@archiver.kernel.org; Mon, 16 Aug 2021 17:07:54 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45616) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mFjoD-0004sy-Hx for qemu-devel@nongnu.org; Mon, 16 Aug 2021 17:06:13 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:20508) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mFjoB-0004qw-DT for qemu-devel@nongnu.org; Mon, 16 Aug 2021 17:06:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1629147970; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=v9lgIWZB9Q254+CZPCuIXjxB1U0EFOzcnpWPNs/WP6M=; b=cvzJr+wBed5cPoVvfpskBA2gNTCVowa39Pp+A4CHXCxbEU1ab0TgE9er5bpnQ/92mQkDKK UCxZkCwf6ZC5qDkEOxXBZw/CPHCXb3eBd8Eyu6S0ILVHqlWTg7S8tvliUN+uTHWYoynAR4 9aM+uU/vjydDxgHDaJ9GFxE/Qj1zbMM= 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-585-cVNYUExAPy2zedTstS7rxg-1; Mon, 16 Aug 2021 17:06:07 -0400 X-MC-Unique: cVNYUExAPy2zedTstS7rxg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A47A3802922; Mon, 16 Aug 2021 21:06:06 +0000 (UTC) Received: from localhost (unknown [10.22.10.28]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3B6A22C00F; Mon, 16 Aug 2021 21:06:06 +0000 (UTC) From: Eduardo Habkost To: qemu-devel@nongnu.org, Peter Maydell Subject: [PULL 1/1] machine: Disallow specifying topology parameters as zero Date: Mon, 16 Aug 2021 17:06:03 -0400 Message-Id: <20210816210603.42337-2-ehabkost@redhat.com> In-Reply-To: <20210816210603.42337-1-ehabkost@redhat.com> References: <20210816210603.42337-1-ehabkost@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 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-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" 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: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.698, 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_H2=-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: Andrew Jones , "Daniel P . Berrange" , Eduardo Habkost , Cornelia Huck , Yanan Wang , Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Yanan Wang In the SMP configuration, we should either provide a topology parameter with a reasonable value (greater than zero) or just omit it and QEMU will compute the missing value. Users should have never provided a configuration with parameters as zero (e.g. -smp 8,sockets=0) which should be treated as invalid. But commit 1e63fe68580 (machine: pass QAPI struct to mc->smp_parse) has added some doc which implied that 'anything=0' is valid and has the same semantics as omitting a parameter. To avoid meaningless configurations possibly introduced by users in the future and consequently a necessary deprecation process, fix the doc and also add the corresponding sanity check. Fixes: 1e63fe68580 (machine: pass QAPI struct to mc->smp_parse) Suggested-by: Andrew Jones Signed-off-by: Yanan Wang Reviewed-by: Daniel P. Berrange Tested-by: Daniel P. Berrange Reviewed-by: Andrew Jones Reviewed-by: Cornelia Huck Message-Id: <20210816024522.143124-2-wangyanan55@huawei.com> Signed-off-by: Eduardo Habkost --- hw/core/machine.c | 14 ++++++++++++++ qapi/machine.json | 6 +++--- qemu-options.hx | 12 +++++++----- 3 files changed, 24 insertions(+), 8 deletions(-) diff --git a/hw/core/machine.c b/hw/core/machine.c index 54e040587dd..a7e119469aa 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -832,6 +832,20 @@ static void machine_set_smp(Object *obj, Visitor *v, const char *name, return; } + /* + * A specified topology parameter must be greater than zero, + * explicit configuration like "cpus=0" is not allowed. + */ + if ((config->has_cpus && config->cpus == 0) || + (config->has_sockets && config->sockets == 0) || + (config->has_dies && config->dies == 0) || + (config->has_cores && config->cores == 0) || + (config->has_threads && config->threads == 0) || + (config->has_maxcpus && config->maxcpus == 0)) { + error_setg(errp, "CPU topology parameters must be greater than zero"); + goto out_free; + } + mc->smp_parse(ms, config, errp); if (*errp) { goto out_free; diff --git a/qapi/machine.json b/qapi/machine.json index c3210ee1fb2..9272cb3cf8b 100644 --- a/qapi/machine.json +++ b/qapi/machine.json @@ -1288,8 +1288,8 @@ ## # @SMPConfiguration: # -# Schema for CPU topology configuration. "0" or a missing value lets -# QEMU figure out a suitable value based on the ones that are provided. +# Schema for CPU topology configuration. A missing value lets QEMU +# figure out a suitable value based on the ones that are provided. # # @cpus: number of virtual CPUs in the virtual machine # @@ -1297,7 +1297,7 @@ # # @dies: number of dies per socket in the CPU topology # -# @cores: number of cores per thread in the CPU topology +# @cores: number of cores per die in the CPU topology # # @threads: number of threads per core in the CPU topology # diff --git a/qemu-options.hx b/qemu-options.hx index 83aa59a920f..aee622f577d 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -227,11 +227,13 @@ SRST of computing the CPU maximum count. Either the initial CPU count, or at least one of the topology parameters - must be specified. Values for any omitted parameters will be computed - from those which are given. Historically preference was given to the - coarsest topology parameters when computing missing values (ie sockets - preferred over cores, which were preferred over threads), however, this - behaviour is considered liable to change. + must be specified. The specified parameters must be greater than zero, + explicit configuration like "cpus=0" is not allowed. Values for any + omitted parameters will be computed from those which are given. + Historically preference was given to the coarsest topology parameters + when computing missing values (ie sockets preferred over cores, which + were preferred over threads), however, this behaviour is considered + liable to change. ERST DEF("numa", HAS_ARG, QEMU_OPTION_numa, -- 2.31.1