From patchwork Thu Apr 30 09:44:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cornelia Huck X-Patchwork-Id: 11519673 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 24402912 for ; Thu, 30 Apr 2020 09:48:15 +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 ED26E2192A for ; Thu, 30 Apr 2020 09:48:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="COv8x8K1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ED26E2192A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:47696 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jU5ni-00044p-1f for patchwork-qemu-devel@patchwork.kernel.org; Thu, 30 Apr 2020 05:48:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48856) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jU5l5-0006BD-3H for qemu-devel@nongnu.org; Thu, 30 Apr 2020 05:45:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.90_1) (envelope-from ) id 1jU5l2-0003m8-8U for qemu-devel@nongnu.org; Thu, 30 Apr 2020 05:45:30 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:29187 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jU5l1-0003l1-Q3 for qemu-devel@nongnu.org; Thu, 30 Apr 2020 05:45:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588239927; 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=spc9pBJlBPplWaKVu6x/YhfSRkiSVaKGDS1D5vyH1X0=; b=COv8x8K1jZiVnlgX6j38N82CuRIAS9jSJBXrY99uX/GcUBjTsLlXlO94Xm4VVOgTFUopi/ HV0qQzTYn7DLoLbUNed6+xbr134mVBKtJW+SohidQM3azdfY6NOlfk0VdNsbUN367vauUw G6BnWTn/Uys2jLuTjMHD733ZaANWCbo= 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-336-dcGm6j8VMPedZThAR1r_dw-1; Thu, 30 Apr 2020 05:45:22 -0400 X-MC-Unique: dcGm6j8VMPedZThAR1r_dw-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 8C491107BEF5; Thu, 30 Apr 2020 09:45:21 +0000 (UTC) Received: from localhost (ovpn-112-226.ams2.redhat.com [10.36.112.226]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B04DE605DD; Thu, 30 Apr 2020 09:45:18 +0000 (UTC) From: Cornelia Huck To: Peter Maydell Subject: [PULL 06/20] s390x: protvirt: Inhibit balloon when switching to protected mode Date: Thu, 30 Apr 2020 11:44:31 +0200 Message-Id: <20200430094445.25943-7-cohuck@redhat.com> In-Reply-To: <20200430094445.25943-1-cohuck@redhat.com> References: <20200430094445.25943-1-cohuck@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=205.139.110.61; envelope-from=cohuck@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/04/30 01:04:40 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.61 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: Janosch Frank , David Hildenbrand , Cornelia Huck , qemu-devel@nongnu.org, Christian Borntraeger , qemu-s390x@nongnu.org, Claudio Imbrenda Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Janosch Frank Ballooning in protected VMs can only be done when the guest shares the pages it gives to the host. If pages are not shared, the integrity checks will fail once those pages have been altered and are given back to the guest. As we currently do not yet have a solution for this we will continue like this: 1. We block ballooning now in QEMU (with this patch). 2. Later we will provide a change to virtio that removes the blocker and adds VIRTIO_F_IOMMU_PLATFORM automatically by QEMU when doing the protvirt switch. This is OK, as the balloon driver in Linux (the only supported guest) will refuse to work with the IOMMU_PLATFORM feature bit set. 3. Later, we can fix the guest balloon driver to accept the IOMMU feature bit and correctly exercise sharing and unsharing of balloon pages. Signed-off-by: Janosch Frank Reviewed-by: David Hildenbrand Reviewed-by: Christian Borntraeger Reviewed-by: Claudio Imbrenda Reviewed-by: Cornelia Huck Message-Id: <20200319131921.2367-6-frankja@linux.ibm.com> Signed-off-by: Cornelia Huck --- hw/s390x/s390-virtio-ccw.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c index e00040a00ba6..db45249320ab 100644 --- a/hw/s390x/s390-virtio-ccw.c +++ b/hw/s390x/s390-virtio-ccw.c @@ -43,6 +43,7 @@ #include "hw/qdev-properties.h" #include "hw/s390x/tod.h" #include "sysemu/sysemu.h" +#include "sysemu/balloon.h" #include "hw/s390x/pv.h" #include #include "migration/blocker.h" @@ -329,6 +330,7 @@ static void s390_machine_unprotect(S390CcwMachineState *ms) ms->pv = false; migrate_del_blocker(pv_mig_blocker); error_free_or_abort(&pv_mig_blocker); + qemu_balloon_inhibit(false); } static int s390_machine_protect(S390CcwMachineState *ms) @@ -336,10 +338,18 @@ static int s390_machine_protect(S390CcwMachineState *ms) Error *local_err = NULL; int rc; + /* + * Ballooning on protected VMs needs support in the guest for + * sharing and unsharing balloon pages. Block ballooning for + * now, until we have a solution to make at least Linux guests + * either support it or fail gracefully. + */ + qemu_balloon_inhibit(true); error_setg(&pv_mig_blocker, "protected VMs are currently not migrateable."); rc = migrate_add_blocker(pv_mig_blocker, &local_err); if (rc) { + qemu_balloon_inhibit(false); error_report_err(local_err); error_free_or_abort(&pv_mig_blocker); return rc; @@ -348,6 +358,7 @@ static int s390_machine_protect(S390CcwMachineState *ms) /* Create SE VM */ rc = s390_pv_vm_enable(); if (rc) { + qemu_balloon_inhibit(false); error_report_err(local_err); migrate_del_blocker(pv_mig_blocker); error_free_or_abort(&pv_mig_blocker);