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 BBE57EC874E for ; Thu, 7 Sep 2023 18:42:59 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qeJxP-0005gb-HF; Thu, 07 Sep 2023 14:42:24 -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 1qeJxM-0005bQ-FP for qemu-devel@nongnu.org; Thu, 07 Sep 2023 14:42:20 -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 1qeJxK-00008M-Bv for qemu-devel@nongnu.org; Thu, 07 Sep 2023 14:42:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694112137; 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=LOt25EnO5qtj39ca67ISqEi98L4xJ4XOy0z+05I9wwI=; b=eQs3kF2lDx30jcV37udOsL7IcJdYBbGlfeGrAlGi9/GSshOTc7YIFi+PILR4JIHI0KosT1 simfYs9nYH6+KDbiGFq3Sz39yuxejwVw+d7/bbacWlSyeT+u89yuzvCxKCkoaz938Pfgv2 c30x5RS2KxxAWzi64ymIwsgsdNtEryw= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-338-KPNWSMX8M1W7MSV-F37fow-1; Thu, 07 Sep 2023 14:42:03 -0400 X-MC-Unique: KPNWSMX8M1W7MSV-F37fow-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 5D3803C11A11; Thu, 7 Sep 2023 18:42:02 +0000 (UTC) Received: from localhost (unknown [10.39.193.223]) by smtp.corp.redhat.com (Postfix) with ESMTP id D461A40C2070; Thu, 7 Sep 2023 18:42:01 +0000 (UTC) Date: Thu, 7 Sep 2023 14:42:00 -0400 From: Stefan Hajnoczi To: Kevin Wolf Cc: qemu-devel@nongnu.org, mst@redhat.com, quintela@redhat.com, peterx@redhat.com, leobras@redhat.com, pbonzini@redhat.com, qemu-block@nongnu.org, qemu-stable@nongnu.org Subject: Re: [PATCH 0/2] virtio: Drop out of coroutine context in virtio_load() Message-ID: <20230907184200.GB1560640@fedora> References: <20230905145002.46391-1-kwolf@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="EpRV4qM7D4OA7J/G" Content-Disposition: inline In-Reply-To: <20230905145002.46391-1-kwolf@redhat.com> X-Scanned-By: MIMEDefang 3.1 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 --EpRV4qM7D4OA7J/G Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Sep 05, 2023 at 04:50:00PM +0200, Kevin Wolf wrote: > This fixes a recently introduced assertion failure that was reported to > happen when migrating virtio-net with a failover. The latent bug that > we're executing code in coroutine context that was never supposed to run > there has existed for a long time. However, the new assertion that > callers of bdrv_graph_rdlock_main_loop() don't run in coroutine context > makes it very visible because it's now always a crash. >=20 > Kevin Wolf (2): > vmstate: Mark VMStateInfo.get/put() coroutine_mixed_fn > virtio: Drop out of coroutine context in virtio_load() >=20 > include/migration/vmstate.h | 8 ++++--- > hw/virtio/virtio.c | 45 ++++++++++++++++++++++++++++++++----- > 2 files changed, 45 insertions(+), 8 deletions(-) This looks like a bandaid for a specific instance of this problem rather than a solution that takes care of the root cause. Is it possible to make VMStateInfo.get/put() consistenty coroutine_fn? Stefan --EpRV4qM7D4OA7J/G Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmT6GXgACgkQnKSrs4Gr c8gRAQgArU7H3LGMXXEao93mxmwrJehbP/Wmh4GlZyBIKMh/qOnx/KM2Kbq/UYuI 7Yc3e5NBUNARCBs1JJm0o9fz2TKcjMf7ATexCs7Zs2SnZuK1h+l1XFum7BXX2Ljo Qx1bK6VkN2K/O53n8wadqmDJcjvfnjdOKzWuW0Kh+8OTPT7ENixsi2fJWU9vCzKd EP157FxacpompWdx8zUP7X6vRS2wLH5gOYiTHjQbxEutjGbIiOxdbEc0XQ/W7XVq 2xjA3ggsaLkQXnWGwmo6Vjb4yn9RVe2RGUWZhGq4dKvaYY1yge4yNe15RZemN92r qKRr45oHhUiJzZV9DGpKagb5hzmhsA== =1kDz -----END PGP SIGNATURE----- --EpRV4qM7D4OA7J/G--