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 80F0DC433EF for ; Tue, 18 Jan 2022 15:43:58 +0000 (UTC) Received: from localhost ([::1]:44044 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1n9qeL-0002zV-9v for qemu-devel@archiver.kernel.org; Tue, 18 Jan 2022 10:43:57 -0500 Received: from eggs.gnu.org ([209.51.188.92]:40688) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n9q5p-0000SL-1E for qemu-devel@nongnu.org; Tue, 18 Jan 2022 10:08:22 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:60739) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n9q5m-0006ch-V6 for qemu-devel@nongnu.org; Tue, 18 Jan 2022 10:08:16 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1642518494; 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=mSqTXeGEA5FR0UobAxa0cVsfO5y4bLI6WLK1pPj15QQ=; b=eVTA4cc4R+KO0sI6jPuNrK4bReDWru7VDLEE+nQ1iXTNasTpB03/MDoG6ed2j5NkMB3vAz xkL6euDVawOTqvM+dTNYyJyw09AQ9rYJDt0B00umdfXiM4Ediwv5cS3Oa762h7WBoE+V+Z Ig/b83PHeh61h9bt8LdGz1r3AWrEiAE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-344-wv3f3PgcPc6_uij8Mnv5OQ-1; Tue, 18 Jan 2022 10:08:11 -0500 X-MC-Unique: wv3f3PgcPc6_uij8Mnv5OQ-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 2D1251014509 for ; Tue, 18 Jan 2022 15:08:10 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.195.156]) by smtp.corp.redhat.com (Postfix) with ESMTP id 507785DBA2; Tue, 18 Jan 2022 15:07:43 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v1 1/2] virtio-mem: Warn if a memory backend with "prealloc=on" is used Date: Tue, 18 Jan 2022 16:07:11 +0100 Message-Id: <20220118150712.139953-2-david@redhat.com> In-Reply-To: <20220118150712.139953-1-david@redhat.com> References: <20220118150712.139953-1-david@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=david@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=170.10.133.124; envelope-from=david@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=-0.7, 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_H3=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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michal Privoznik , Juan Quintela , "Michael S . Tsirkin" , "Dr . David Alan Gilbert" , David Hildenbrand Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" "prealloc=on" for the memory backend does not work as expected, as virtio-mem will simply discard all preallocated memory immediately again. In the best case, it's an expensive NOP. In the worst case, it's an unexpected allocation error. Instead, "prealloc=on" should be specified for the virtio-mem device only, such that virtio-mem will try preallocating memory before plugging memory dynamically to the guest. Signed-off-by: David Hildenbrand --- hw/virtio/virtio-mem.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 04c223b0c9..6c337db0a7 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -765,6 +765,13 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) return; } + if (vmem->memdev->prealloc) { + warn_report("'%s' property specifies a memdev with preallocation" + " enabled: %s. Instead, specify 'prealloc=on' for the" + " virtio-mem device. ", VIRTIO_MEM_MEMDEV_PROP, + object_get_canonical_path_component(OBJECT(vmem->memdev))); + } + if ((nb_numa_nodes && vmem->node >= nb_numa_nodes) || (!nb_numa_nodes && vmem->node)) { error_setg(errp, "'%s' property has value '%" PRIu32 "', which exceeds" -- 2.34.1