From patchwork Fri Oct 15 10:49:09 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gavin Shan X-Patchwork-Id: 12561015 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C181AC433F5 for ; Fri, 15 Oct 2021 10:50:56 +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 4E49061056 for ; Fri, 15 Oct 2021 10:50:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 4E49061056 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]:50318 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mbKnf-0000H0-4p for qemu-devel@archiver.kernel.org; Fri, 15 Oct 2021 06:50:55 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:59922) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mbKmH-0007eK-Ct for qemu-devel@nongnu.org; Fri, 15 Oct 2021 06:49:29 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:42671) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mbKmE-0000ih-8e for qemu-devel@nongnu.org; Fri, 15 Oct 2021 06:49:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634294961; 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; bh=maTTtXdlSTQj8q1wAof5H5YOOBc3riqhlbyW4EBa6xM=; b=LG0BKFiItT58GUuZyv/K+BEnmpDclCT19QDU8JhJFBGCL9mcVPb6fqqvLit/CVoiMYIJF5 CIOzvgyL216gOVVALNGUo3yNgWcH7KXMjGFBV9aSsTnPNPWXXR+0oMNmCqVJ/y/TQhGmR+ PTllILHam7qETD5sVjIqbrITnZD5KwQ= 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-352-aTJgCOKfPe6_JFON83Nllg-1; Fri, 15 Oct 2021 06:49:18 -0400 X-MC-Unique: aTJgCOKfPe6_JFON83Nllg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4547218D6A32; Fri, 15 Oct 2021 10:49:17 +0000 (UTC) Received: from gshan.redhat.com (vpn2-54-38.bne.redhat.com [10.64.54.38]) by smtp.corp.redhat.com (Postfix) with ESMTP id BD00410013D7; Fri, 15 Oct 2021 10:49:13 +0000 (UTC) From: Gavin Shan To: qemu-arm@nongnu.org Subject: [PATCH v4] hw/arm/virt: Don't create device-tree node for empty NUMA node Date: Fri, 15 Oct 2021 18:49:09 +0800 Message-Id: <20211015104909.16722-1-gshan@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=gshan@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.133.124; envelope-from=gshan@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.049, 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: robh@kernel.org, drjones@redhat.com, qemu-riscv@nongnu.org, ehabkost@redhat.com, peter.maydell@linaro.org, qemu-devel@nongnu.org, shan.gavin@gmail.com, imammedo@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The empty NUMA node, where no memory resides, are allowed. For example, the following command line specifies two empty NUMA nodes. With this, QEMU fails to boot because of the conflicting device-tree node names, as the following error message indicates. /home/gavin/sandbox/qemu.main/build/qemu-system-aarch64 \ -accel kvm -machine virt,gic-version=host \ -cpu host -smp 4,sockets=2,cores=2,threads=1 \ -m 1024M,slots=16,maxmem=64G \ -object memory-backend-ram,id=mem0,size=512M \ -object memory-backend-ram,id=mem1,size=512M \ -numa node,nodeid=0,cpus=0-1,memdev=mem0 \ -numa node,nodeid=1,cpus=2-3,memdev=mem1 \ -numa node,nodeid=2 \ -numa node,nodeid=3 : qemu-system-aarch64: FDT: Failed to create subnode /memory@80000000: FDT_ERR_EXISTS As specified by linux device-tree binding document, the device-tree nodes for these empty NUMA nodes shouldn't be generated. However, the corresponding NUMA node IDs should be included in the distance map. As the memory hotplug through device-tree on ARM64 isn't existing so far, it's pointless to expose the empty NUMA nodes through device-tree. So this simply skips populating the device-tree nodes for these empty NUMA nodes to avoid the error, so that QEMU can be started successfully. Signed-off-by: Gavin Shan --- v4: Drop patch to enforce distance-map as memory hotplug through device-tree is never supported on ARM64. It's pointless to expose these empty NUMA nodes. Besides, comments added to explain the code changes included in this patch as Drew suggested. --- hw/arm/boot.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/hw/arm/boot.c b/hw/arm/boot.c index 57efb61ee4..e05c1c149c 100644 --- a/hw/arm/boot.c +++ b/hw/arm/boot.c @@ -599,10 +599,24 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo, } g_strfreev(node_path); + /* + * According to Linux NUMA binding document, the device tree nodes + * for the empty NUMA nodes shouldn't be generated, but their NUMA + * node IDs should be included in the distance map instead. However, + * it's pointless to expose the empty NUMA nodes as memory hotplug + * through device tree is never supported. We simply skip generating + * their device tree nodes to avoid the unexpected device tree + * generating failure due to the duplicated names of these empty + * NUMA nodes. + */ if (ms->numa_state != NULL && ms->numa_state->num_nodes > 0) { mem_base = binfo->loader_start; for (i = 0; i < ms->numa_state->num_nodes; i++) { mem_len = ms->numa_state->nodes[i].node_mem; + if (!mem_len) { + continue; + } + rc = fdt_add_memory_node(fdt, acells, mem_base, scells, mem_len, i); if (rc < 0) {