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 X-Spam-Level: X-Spam-Status: No, score=-0.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EA784C3B18F for ; Thu, 13 Feb 2020 23:02:34 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id B8D2020675 for ; Thu, 13 Feb 2020 23:02:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.b="qD8qhRs6" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B8D2020675 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:60608 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j2NVB-0004mU-PG for qemu-devel@archiver.kernel.org; Thu, 13 Feb 2020 18:02:33 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:51098) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j2NQy-00075R-Mw for qemu-devel@nongnu.org; Thu, 13 Feb 2020 17:58:13 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j2NQx-0006V9-8x for qemu-devel@nongnu.org; Thu, 13 Feb 2020 17:58:12 -0500 Received: from bilbo.ozlabs.org ([2401:3900:2:1::2]:39985 helo=ozlabs.org) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j2NQv-0006Gt-PS; Thu, 13 Feb 2020 17:58:10 -0500 Received: by ozlabs.org (Postfix, from userid 1007) id 48JX3Z6Y7dz9sRG; Fri, 14 Feb 2020 09:58:02 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1581634682; bh=diOphC0RvZAzk7sd5XPNf8YAh2BCWesdZSoV6j22MaM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qD8qhRs6zuK3fcjQRL/o3f3ozpXTYjbqWXUGHktynbVSnv5hygwXzpKX7wRbSNvto ZHYi1Bv5bvokdJ73XNuQ5Krs/fOx5wjnRA42D8J6bOGdT5wVDABm6xfq827mLZXx0a H5bEs0xYkPNbfdgOKYyhnLHUCDiajmn0pBsXU4s8= Date: Fri, 14 Feb 2020 09:57:56 +1100 From: David Gibson To: Greg Kurz Subject: Re: [PATCH v2 0/2] spapr: Use vIOMMU translation for virtio by default Message-ID: <20200213225756.GI124369@umbus.fritz.box> References: <20200213005837.131791-1-david@gibson.dropbear.id.au> <20200213124643.7b205d44@bahia.lan> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="vs0rQTeTompTJjtd" Content-Disposition: inline In-Reply-To: <20200213124643.7b205d44@bahia.lan> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2401:3900:2:1::2 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: pair@us.ibm.com, mst@redhat.com, aik@ozlabs.ru, qemu-devel@nongnu.org, qemu-ppc@nongnu.org, clg@kaod.org, mdroth@us.ibm.com, paulus@samba.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --vs0rQTeTompTJjtd Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Feb 13, 2020 at 12:46:43PM +0100, Greg Kurz wrote: > On Thu, 13 Feb 2020 11:58:35 +1100 > David Gibson wrote: >=20 > > Upcoming Secure VM support for pSeries machines introduces some > > complications for virtio, since the transfer buffers need to be > > explicitly shared so that the hypervisor can access them. > >=20 > > While it's not strictly speaking dependent on it, the fact that virtio > > devices bypass normal platform IOMMU translation complicates the issue > > on the guest side. Since there are some significan downsides to > > bypassing the vIOMMU anyway, let's just disable that. > >=20 > > There's already a flag to do this in virtio, just turn it on by > > default for forthcoming pseries machine types. > >=20 > > Any opinions on whether dropping support for the older guest kernels > > is acceptable at this point? > >=20 >=20 > As expected, this breaks compatibility with existing RHEL 6.10 guests. Ea= ch > patch in this series requires an extra -global option to be specified on > the command line in order to boot successfully. >=20 > Patch 1: -global virtio-pci.disable-legacy=3Dauto > Patch 2: -global virtio-pci.iommu_platform=3Doff Right, or setting an older machine type. > As seen on the RH site [1], RHEL6 will reach "End of Maintenance Support > or Maintenance Support 2 (Product retirement)" on November 30, 2020 and > "End of Extended Life-cycle Support" on June 30, 2024. >=20 > Not sure if it's okay to drop support for RHEL6 this soon. Hm, yeah. I'm happy enough to do this upstream, downstream will require some discussion. > RHEL 7.7 guests seem to be unaffected. Yeah, I already checked and RHEL7 has backported support for modern virtio and the iommu platform flag. >=20 > [1] https://access.redhat.com/support/policy/updates/errata/#Life_Cycle_D= ates >=20 > > Changes since v1: > > * Added information on which guest kernel versions will no longer > > work with these changes > > * Use Michael Tsirkin's suggested better way of handling the machine > > type change > >=20 > > David Gibson (2): > > spapr: Disable legacy virtio devices for pseries-5.0 and later > > spapr: Enable virtio iommu_platform=3Don by default > >=20 > > hw/ppc/spapr.c | 16 +++++++++++++++- > > 1 file changed, 15 insertions(+), 1 deletion(-) > >=20 >=20 --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --vs0rQTeTompTJjtd Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAl5F1HQACgkQbDjKyiDZ s5Kp8BAA5s7lU2O9pHRUGE1w1AN9HLT/I2wsICxTCpqzYDu1TcZky+lZVaGa5u+8 edLRQogRxd9vkK7o4QEAbsJVr705X8tR6C5iF4ErV1vkmxljFmMSMfpFg/qVPcXd sSXo/Owdio7dQRPlHPGc7vXFlPWsihcOKIAvX4Sy8uij7iA+2/pqIk81jJoUNPaD /9cFSNSHlqtvHbN+Sqzr06RYMcmRIrSMOFsQxalmiSgw/Xcujf5nWnkhEMRE0j1p eT2N2EWM76N8I9pU4lKJNx4zwzHtJeJvQGFXEiTVz1FbkWaJmBEnN+V0l/+R/nRn wONTAaQO+gR/PAaqSuoLLTUbErR4+yWDuuwsJ8vS69aRuHl9BexjD1AzKVSC9D6i PU+HNboNdMfjbuQe9NcKjPU2UBdbrRpPGRbmKWM5V6mtCSincIfkR3O4IcQ9Lblf CCGkNPAKswEtoQQEFkGI+LPIkhMn2Exwg49oNH61CT9epLrTamysheijozxLAo3O HVLZHD9JKyD8rIU0jYMq3N5OmdS8iJZ1zlj9jQWjpneRL9abOflAvLYujRzwtFH2 VhxnsJ0ToStrc42ZgxLZNeeqDXc5Hx/ajl4pVWvPisJdPEgAfg9ao6K2b4rQjf7h 60mYOz9rv/FUfpiNZ8UvtL85OcncvnyJby11/9E2u0wkN3tq628= =K/Ky -----END PGP SIGNATURE----- --vs0rQTeTompTJjtd--