From patchwork Wed Jun 10 11:54:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 11597607 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 00B3D138C for ; Wed, 10 Jun 2020 11:55:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD79C20760 for ; Wed, 10 Jun 2020 11:55:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Ea6ADcck" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728730AbgFJLzD (ORCPT ); Wed, 10 Jun 2020 07:55:03 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:58108 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728751AbgFJLzC (ORCPT ); Wed, 10 Jun 2020 07:55:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591790101; 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=VUu0CYVglzX/Ll9iBfJF7XJmcLsniLRcSuurJhAdw+U=; b=Ea6ADcck4+L0T/aY0Dc5tihNuThdNN1WZHcLDNUcMnTm7NfhBlAnuVVKNkl1B9/ZYWveQK ngsBgzM1508m5EL/MkIZVeP75obvDG3LVvdy5099Bsw8BGFVGrwZ6z7n96taZahGmkzLp+ y3ivy4F3cpuFUuS6Gg/1hL2n4fzMxIg= 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-198-nG8aSuP-M3m0pAJ0p-BRKg-1; Wed, 10 Jun 2020 07:54:57 -0400 X-MC-Unique: nG8aSuP-M3m0pAJ0p-BRKg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 57E4C8014D4; Wed, 10 Jun 2020 11:54:56 +0000 (UTC) Received: from t480s.redhat.com (ovpn-114-42.ams2.redhat.com [10.36.114.42]) by smtp.corp.redhat.com (Postfix) with ESMTP id CEBC65D9D3; Wed, 10 Jun 2020 11:54:53 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: kvm@vger.kernel.org, qemu-s390x@nongnu.org, Richard Henderson , Paolo Bonzini , "Dr . David Alan Gilbert" , Eduardo Habkost , "Michael S . Tsirkin" , David Hildenbrand , Cornelia Huck , Halil Pasic , Christian Borntraeger , Janosch Frank Subject: [PATCH v4 04/21] s390x/pv: Convert to ram_block_discard_disable() Date: Wed, 10 Jun 2020 13:54:02 +0200 Message-Id: <20200610115419.51688-5-david@redhat.com> In-Reply-To: <20200610115419.51688-1-david@redhat.com> References: <20200610115419.51688-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Discarding RAM does not work as expected with protected VMs. Let's switch to ram_block_discard_disable() for now, as we want to get rid of qemu_balloon_inhibit(). Note that it will currently never fail, but might fail in the future with new technologies (e.g., virtio-mem). Cc: Richard Henderson Cc: Cornelia Huck Cc: Halil Pasic Cc: Christian Borntraeger Cc: Janosch Frank Signed-off-by: David Hildenbrand Acked-by: Cornelia Huck --- hw/s390x/s390-virtio-ccw.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c index 60b16fef77..c985bb56eb 100644 --- a/hw/s390x/s390-virtio-ccw.c +++ b/hw/s390x/s390-virtio-ccw.c @@ -43,7 +43,6 @@ #include "hw/qdev-properties.h" #include "hw/s390x/tod.h" #include "sysemu/sysemu.h" -#include "sysemu/balloon.h" #include "hw/s390x/pv.h" #include "migration/blocker.h" @@ -329,7 +328,7 @@ 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); + ram_block_discard_disable(false); } static int s390_machine_protect(S390CcwMachineState *ms) @@ -338,17 +337,22 @@ static int s390_machine_protect(S390CcwMachineState *ms) 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. + * Discarding of memory in RAM blocks does not work as expected with + * protected VMs. Sharing and unsharing pages would be required. Disable + * it for now, until until we have a solution to make at least Linux + * guests either support it (e.g., virtio-balloon) or fail gracefully. */ - qemu_balloon_inhibit(true); + rc = ram_block_discard_disable(true); + if (rc) { + error_report("protected VMs: cannot disable RAM discard"); + return rc; + } + 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); + ram_block_discard_disable(false); error_report_err(local_err); error_free_or_abort(&pv_mig_blocker); return rc; @@ -357,7 +361,7 @@ static int s390_machine_protect(S390CcwMachineState *ms) /* Create SE VM */ rc = s390_pv_vm_enable(); if (rc) { - qemu_balloon_inhibit(false); + ram_block_discard_disable(false); migrate_del_blocker(pv_mig_blocker); error_free_or_abort(&pv_mig_blocker); return rc;