From mboxrd@z Thu Jan 1 00:00:00 1970 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id D3A2FCDB474 for ; Tue, 17 Oct 2023 13:48:52 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qskPt-0005kQ-Jn; Tue, 17 Oct 2023 09:47:25 -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 1qskPl-0005jT-Ei for qemu-devel@nongnu.org; Tue, 17 Oct 2023 09:47:21 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qskPj-0005Aq-Gz for qemu-devel@nongnu.org; Tue, 17 Oct 2023 09:47:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1697550433; 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: in-reply-to:in-reply-to:references:references; bh=zSIy4H06gJX306y3lD4NRcTPZPd1ShxNVwyaQXv5bEc=; b=WK6rBE8a2lri9cTxrw0PWosxUgVvQLZLOcQgwe8B8W3oIsVC/yZuQhXXLB767c0zuHNPYU k8RWyRq6ggNcstLcpfTXh9SCrTj06Gl0w1bj+nL61d+y+WzLPHoDD7v76MOcACrjdWeVJL 9WvXDr1PAiZPJIxTh6ILYV9zkJkmFt4= 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-486-qkRbto6AOlagGYYufdCeaA-1; Tue, 17 Oct 2023 09:46:55 -0400 X-MC-Unique: qkRbto6AOlagGYYufdCeaA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 48EAE81D9ED; Tue, 17 Oct 2023 13:46:55 +0000 (UTC) Received: from localhost (unknown [10.39.192.57]) by smtp.corp.redhat.com (Postfix) with ESMTP id A5A842BA; Tue, 17 Oct 2023 13:46:54 +0000 (UTC) Date: Tue, 17 Oct 2023 09:46:53 -0400 From: Stefan Hajnoczi To: Kevin Wolf Cc: Fiona Ebner , qemu-devel@nongnu.org, "Michael S. Tsirkin" , qemu-block@nongnu.org, Hanna Reitz , hujian Subject: Re: [PULL 1/1] virtio-blk: don't start dataplane during the stop of dataplane Message-ID: <20231017134653.GB211967@fedora> References: <20231016194028.163610-1-stefanha@redhat.com> <20231016194028.163610-2-stefanha@redhat.com> <851be4cf-d3e1-4031-bc5a-95fbef1ce21f@proxmox.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="hRY23LTO+7V/JsRy" Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.1 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@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, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org --hRY23LTO+7V/JsRy Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Oct 17, 2023 at 12:02:26PM +0200, Kevin Wolf wrote: > Am 17.10.2023 um 11:01 hat Fiona Ebner geschrieben: > > Am 16.10.23 um 21:40 schrieb Stefan Hajnoczi: > > > diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c > > > index 39e7f23fab..c2d59389cb 100644 > > > --- a/hw/block/virtio-blk.c > > > +++ b/hw/block/virtio-blk.c > > > @@ -1166,7 +1166,7 @@ static void virtio_blk_handle_output(VirtIODevi= ce *vdev, VirtQueue *vq) > > > { > > > VirtIOBlock *s =3D (VirtIOBlock *)vdev; > > > =20 > > > - if (s->dataplane && !s->dataplane_started) { > > > + if (s->dataplane && !s->dataplane_started && !s->stopping) { > >=20 > > Isn't 'stopping' a property of VirtIOBlockDataPlane? Here, s is VirtIOB= lock. >=20 > Indeed, this patch doesn't even build for me. >=20 > However, even if we wrote !s->dataplane->stopping, would it really be > right to be handling I/O in the main thread while the dataplane hasn't > stopped yet? At least without all the multiqueue changes, it's not > obvious to me that it can't cause problems. Unfortunately, the commit > message doesn't say anything about why it's safe. Thanks for pointing these things out, Fiona and Kevin. I've dropped the patch for now. Stefan --hRY23LTO+7V/JsRy Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmUukE0ACgkQnKSrs4Gr c8iBFQgAoOl+vvXlxZeeXqtz5Clp86+x7otHXsqAE5bl8i2vfa/P0ki3VAOBoGiq 2ZjAaK8AYVeI6ROJli64YaysuyRdzeR9WJu5Ux8VyqmgC+px6tqlCsxdQn8CMNX+ kflJ9Dbqw5a+OKqrA0rhs3zvdXFyVQd/U+cnMrt25LZNzDQQpjkeH4cvizu1CyMG CdcsTz8dosTGfG1W++de1uI1wD6BwBzN81b/npAOoOsuQOzj6AgGW9TQCq3b6iEI wG9tu6EcuNPk/a6D7eAQtbF/Ju2N8AKefKkfrF5/izscMeRoMkQRkgRjAESog5gR DYN14Iv1Ok1kvuuXwaal5TntfpFl5Q== =J8yX -----END PGP SIGNATURE----- --hRY23LTO+7V/JsRy--