From nobody Tue Feb 10 16:18:55 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1686668884; cv=none; d=zohomail.com; s=zohoarc; b=GL32ACpaG+lDAjsfoMsuJPflPjZxDX7GVTiVUozGHRZA3JvQ8LZSi0T9xPrOfwyY3e7SAtbhFWVc+K3ICNazj/naqhiuOl5uqbK96WxLgnF8EfvmxL0KsZ8Hjl2kZmehf65IE7okzFhCH/Mcpj7++1jzz1RiaaYvwOxhzw6CYkc= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1686668884; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=C3q1VOCi3VSeulPig7kmaGVgtQD3yY/HQD0PCA5v3u8=; b=f+rmzWACv/uQhSCcdP8d9m+9sVi6bfH4y3a5zfVKiYyb87B/71YMQ5Zc1waqmy3oWy5K0hsm27eMXyvpxNDE28zKWICdbujFdBDZTbk+X72dHVKwiJlhS4xt6zWX/31sAUoxnuu12YB9mT2JgsT5RQoh3mL0kGiXNpFTSll33PQ= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1686668884136735.9367159778913; Tue, 13 Jun 2023 08:08:04 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q95Yu-0004sV-Ge; Tue, 13 Jun 2023 11:04:00 -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 1q95Y5-0003xE-86 for qemu-devel@nongnu.org; Tue, 13 Jun 2023 11:03:11 -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 1q95Xd-0008U6-Is for qemu-devel@nongnu.org; Tue, 13 Jun 2023 11:02:42 -0400 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-623-DNgGdphGP1WvPmgYP5F72w-1; Tue, 13 Jun 2023 11:02:15 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 8F85080349B; Tue, 13 Jun 2023 15:02:14 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.192.249]) by smtp.corp.redhat.com (Postfix) with ESMTP id E66A140B4CD6; Tue, 13 Jun 2023 15:02:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1686668551; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=C3q1VOCi3VSeulPig7kmaGVgtQD3yY/HQD0PCA5v3u8=; b=MYRauKCNx8v4RbRA7p2Zyj61lBIHWKy+RuGd4EhoSRt5evc/xAVBQ5DMThDJEF7O3wbkui nvJW3yE5I4MfGpFQa2c1i2T8A1Xv4yH62Dmp0tdl75q17Gh48rIrwB3/t5ZyuLq5+yTJW3 StlD937s88mqqtgvQXTQmzeHtiw+B3c= X-MC-Unique: DNgGdphGP1WvPmgYP5F72w-1 From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , Peter Maydell , Paolo Bonzini , Richard Henderson , Eduardo Habkost , "Michael S. Tsirkin" , Marcel Apfelbaum , Igor Mammedov , qemu-arm@nongnu.org, Gavin Shan Subject: [PATCH v1 1/5] pc: Properly handle unplug of virtio based memory devices Date: Tue, 13 Jun 2023 17:02:06 +0200 Message-Id: <20230613150210.449406-2-david@redhat.com> In-Reply-To: <20230613150210.449406-1-david@redhat.com> References: <20230613150210.449406-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 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_NONE=-0.0001, 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: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1686668936080100001 Content-Type: text/plain; charset="utf-8" While we fence unplug requests from the outside, the VM can still trigger unplug of virtio based memory devices, for example, in Linux doing: # echo 0 > /sys/bus/pci/slots/3/power While doing that is not really expected to work without harming the guest OS (e.g., removing a virtio-mem device while it still provides memory), let's make sure that we properly handle it on the QEMU side. We'll support unplugging of virtio-mem devices in some configurations next. Signed-off-by: David Hildenbrand --- hw/i386/pc.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/hw/i386/pc.c b/hw/i386/pc.c index fc52772fdd..fdd7062929 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -1559,7 +1559,25 @@ static void pc_virtio_md_pci_unplug_request(HotplugH= andler *hotplug_dev, static void pc_virtio_md_pci_unplug(HotplugHandler *hotplug_dev, DeviceState *dev, Error **errp) { - /* We don't support hot unplug of virtio based memory devices */ + HotplugHandler *hotplug_dev2 =3D qdev_get_bus_hotplug_handler(dev); + Error *local_err =3D NULL; + + /* Unplug the memory device while it is still realized. */ + memory_device_unplug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev)); + + if (hotplug_dev2) { + hotplug_handler_unplug(hotplug_dev2, dev, &local_err); + if (local_err) { + /* Not expected to fail ... but still try to recover. */ + memory_device_plug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev)); + error_propagate(errp, local_err); + return; + } + } else { + /* Very unexpected, but let's just try to do the right thing. */ + warn_report("Unexpected unplug of virtio based memory device"); + qdev_unrealize(dev); + } } =20 static void pc_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev, --=20 2.40.1