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 27293C4332F for ; Wed, 13 Dec 2023 21:20:09 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rDWdq-0000NL-1a; Wed, 13 Dec 2023 16:19:42 -0500 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 1rDWdi-0000MV-Am for qemu-devel@nongnu.org; Wed, 13 Dec 2023 16:19:36 -0500 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 1rDWdg-00075a-Qh for qemu-devel@nongnu.org; Wed, 13 Dec 2023 16:19:34 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1702502371; 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=l0i/cnUa92G7edkpsOhfGpbmCDze0Op1afLYP08/qcM=; b=B5mEqLflyzKu/BTpgmL4tYf7fObYXz0Cz45K7QQhTc/zW1ChmF+9pOUDuM+hTYEise+kCh ZdrzR0mMIcag/YjJbtVmTIFyK+NtB3s0Tik/BP2Iiglu1ZL+5VR83P3AUcCR8DK5CKAhIJ uARTM9cC6UidKBjyWn0+dSwyNBhmN3c= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-314-Zw2sKnTyN96Sek_VdIXT-A-1; Wed, 13 Dec 2023 16:19:28 -0500 X-MC-Unique: Zw2sKnTyN96Sek_VdIXT-A-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 9E7771C0512B; Wed, 13 Dec 2023 21:19:27 +0000 (UTC) Received: from localhost (unknown [10.39.195.82]) by smtp.corp.redhat.com (Postfix) with ESMTP id 068351121306; Wed, 13 Dec 2023 21:19:26 +0000 (UTC) Date: Wed, 13 Dec 2023 16:19:25 -0500 From: Stefan Hajnoczi To: Fiona Ebner Cc: Kevin Wolf , qemu-block@nongnu.org, richard.henderson@linaro.org, qemu-devel@nongnu.org, Thomas Lamprecht , Hanna Reitz , Paolo Bonzini , Fam Zheng , "Michael S . Tsirkin" Subject: Re: [PULL 29/32] virtio-blk: implement BlockDevOps->drained_begin() Message-ID: <20231213211925.GA1597699@fedora> References: <20230530163239.576632-1-kwolf@redhat.com> <20230530163239.576632-30-kwolf@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="VwJX82GWxvCYx28r" Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.3 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, T_SCC_BODY_TEXT_LINE=-0.01 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 --VwJX82GWxvCYx28r Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Dec 11, 2023 at 11:48:05AM +0100, Fiona Ebner wrote: > Am 08.12.23 um 09:32 schrieb Kevin Wolf: > >=20 > > I'm not involved in it myself, but the kind of theme reminds me of this > > downstream bug that Hanna analysed recently: > >=20 > > https://issues.redhat.com/browse/RHEL-3934 > >=20 > > Does it look like the same root cause to you? > >=20 >=20 > Thank you for the reference! Yes, that does sound like the same root > cause. And the workaround I ended up with is also very similar, but it > was missing kicking the virt queue. Hi Fiona, I sent an RFC series that calls io_poll_end() from the AioContext's home thread: https://lore.kernel.org/qemu-devel/20231213211544.1601971-1-stefanha@redhat= =2Ecom/T/#t If you get a chance to test if it fixes the bug that would be great. It is based on my AioContext lock removal patch series: https://lore.kernel.org/qemu-devel/20231205182011.1976568-1-stefanha@redhat= =2Ecom/ Thanks, Stefan --VwJX82GWxvCYx28r Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmV6H90ACgkQnKSrs4Gr c8hwsgf/UvGXrQ3505Tv6MjOHvd5f5wDkJPd8s2j58SfeneCbV7zpzGDZ/HoqBzM YNe7zWgqwiamCEqVSOIWhNKjGStVaZZwAPcAFhiX7cVY0uEX/Vo/YYZg4/xH99PV ow3mJ6SIQDEVdJ9q8S5IcL2HuUFTfeMXdcvnvdiWAotbuB6ewsOJPqv68dpWWWzc aDzpkBUy1wYtNtIJP0pvidGCa9Xzmzb55B+douU0qX1JSzwDqZEtU7hh1KPQqGRx +jB+tHGq7/UePaqN/odapILy770sQ1ygmDv1pzprqD9FE/McE2edobe80fzXWbXC SgtqJJBPeEbhepW5YtPBU1DowknGzQ== =U4K+ -----END PGP SIGNATURE----- --VwJX82GWxvCYx28r--