From nobody Sat Nov 8 10:13:38 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.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; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (209.51.188.17 [209.51.188.17]) by mx.zohomail.com with SMTPS id 1549980863709346.65045324083394; Tue, 12 Feb 2019 06:14:23 -0800 (PST) Received: from localhost ([127.0.0.1]:40336 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gtYpG-00083l-U3 for importer@patchew.org; Tue, 12 Feb 2019 09:14:18 -0500 Received: from eggs.gnu.org ([209.51.188.92]:51474) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gtYht-00022p-HR for qemu-devel@nongnu.org; Tue, 12 Feb 2019 09:06:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gtYhs-0006qW-Bf for qemu-devel@nongnu.org; Tue, 12 Feb 2019 09:06:41 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43180) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gtYhm-0006Tu-ES; Tue, 12 Feb 2019 09:06:34 -0500 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 mx1.redhat.com (Postfix) with ESMTPS id 55029C05093A; Tue, 12 Feb 2019 14:06:16 +0000 (UTC) Received: from localhost (unknown [10.64.242.44]) by smtp.corp.redhat.com (Postfix) with ESMTP id C9ADA5D962; Tue, 12 Feb 2019 14:06:15 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org, Peter Maydell Date: Tue, 12 Feb 2019 22:03:27 +0800 Message-Id: <20190212140330.1467-4-stefanha@redhat.com> In-Reply-To: <20190212140330.1467-1-stefanha@redhat.com> References: <20190212140330.1467-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 12 Feb 2019 14:06:16 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [RFC PULL 3/6] virtio-blk: add "discard" and "write-zeroes" properties X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pankaj Gupta , qemu-block@nongnu.org, "Michael S . Tsirkin" , "Dr . David Alan Gilbert" , Stefan Hajnoczi , sgarzare@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" From: Stefano Garzarella In order to avoid migration issues, we enable DISCARD and WRITE_ZEROES features only for machine type >=3D 4.0 As discussed with Michael S. Tsirkin and Stefan Hajnoczi on the list [1], DISCARD operation should not have security implications (eg. page cache attacks), so we can enable it by default. [1] https://lists.gnu.org/archive/html/qemu-devel/2019-02/msg00504.html Suggested-by: Dr. David Alan Gilbert Reviewed-by: Michael S. Tsirkin Reviewed-by: Stefan Hajnoczi Signed-off-by: Stefano Garzarella Acked-by: Pankaj Gupta Message-id: 20190208134950.187665-4-sgarzare@redhat.com Signed-off-by: Stefan Hajnoczi --- hw/block/virtio-blk.c | 4 ++++ hw/core/machine.c | 2 ++ 2 files changed, 6 insertions(+) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 938273c63c..6f2e86264d 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -1026,6 +1026,10 @@ static Property virtio_blk_properties[] =3D { DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 128), DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD, IOThread *), + DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features, + VIRTIO_BLK_F_DISCARD, true), + DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features, + VIRTIO_BLK_F_WRITE_ZEROES, true), DEFINE_PROP_END_OF_LIST(), }; =20 diff --git a/hw/core/machine.c b/hw/core/machine.c index 077fbd182a..766ca5899d 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -33,6 +33,8 @@ GlobalProperty hw_compat_3_1[] =3D { { "usb-kbd", "serial", "42" }, { "usb-mouse", "serial", "42" }, { "usb-kbd", "serial", "42" }, + { "virtio-blk-device", "discard", "false" }, + { "virtio-blk-device", "write-zeroes", "false" }, }; const size_t hw_compat_3_1_len =3D G_N_ELEMENTS(hw_compat_3_1); =20 --=20 2.20.1