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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 6B260C35247 for ; Wed, 5 Feb 2020 17:00:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 31CBA20674 for ; Wed, 5 Feb 2020 17:00:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ejvBc8f2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727457AbgBERA6 (ORCPT ); Wed, 5 Feb 2020 12:00:58 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:37848 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727303AbgBERA6 (ORCPT ); Wed, 5 Feb 2020 12:00:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580922056; 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:openpgp:openpgp; bh=2HjIC22WDDe89RXOUmc9CxopsRp0jRMwPHeEjAlYVeU=; b=ejvBc8f27NLfguaWIJJCUpquEtbgKfMQB99lBvU0J6JwXPwxGVJmQuyB2xUk1Ceru8sGoG wdVlOKgYp84XiWpYJDz1M7r4/ia+slpcXhSsIG0Lbcs1sWAjgi2L8bwV/4GQ81k0RA4HEQ HoRnZF1Jqn6bb5UNWh/O4WJboprzW0I= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-273-BMcPtnimOdSt3LYryJbLwg-1; Wed, 05 Feb 2020 12:00:50 -0500 X-MC-Unique: BMcPtnimOdSt3LYryJbLwg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1A2251081FA3; Wed, 5 Feb 2020 17:00:49 +0000 (UTC) Received: from thuth.remote.csb (ovpn-116-186.ams2.redhat.com [10.36.116.186]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B58AA86C4A; Wed, 5 Feb 2020 17:00:39 +0000 (UTC) Subject: Re: [RFCv2 21/37] KVM: S390: protvirt: Introduce instruction data area bounce buffer To: Janosch Frank , Christian Borntraeger , Janosch Frank Cc: KVM , Cornelia Huck , David Hildenbrand , Ulrich Weigand , Claudio Imbrenda , Andrea Arcangeli References: <20200203131957.383915-1-borntraeger@de.ibm.com> <20200203131957.383915-22-borntraeger@de.ibm.com> <55220810-3e2f-6312-4199-2afb583d9ff2@redhat.com> <47593ba3-43c0-c7d3-2f4f-e649e21cb29a@linux.ibm.com> From: Thomas Huth Openpgp: preference=signencrypt Message-ID: <7539e1d3-79c6-3581-b3fb-afa545bb81d2@redhat.com> Date: Wed, 5 Feb 2020 18:00:31 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <47593ba3-43c0-c7d3-2f4f-e649e21cb29a@linux.ibm.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="or1zbOiroipTYUWf2sALfNaXVNimODY4y" Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --or1zbOiroipTYUWf2sALfNaXVNimODY4y Content-Type: multipart/mixed; boundary="Sx0zEr1v6Od5seHZBRbZigVRnETzvTDh3"; protected-headers="v1" From: Thomas Huth To: Janosch Frank , Christian Borntraeger , Janosch Frank Cc: KVM , Cornelia Huck , David Hildenbrand , Ulrich Weigand , Claudio Imbrenda , Andrea Arcangeli Message-ID: <7539e1d3-79c6-3581-b3fb-afa545bb81d2@redhat.com> Subject: Re: [RFCv2 21/37] KVM: S390: protvirt: Introduce instruction data area bounce buffer References: <20200203131957.383915-1-borntraeger@de.ibm.com> <20200203131957.383915-22-borntraeger@de.ibm.com> <55220810-3e2f-6312-4199-2afb583d9ff2@redhat.com> <47593ba3-43c0-c7d3-2f4f-e649e21cb29a@linux.ibm.com> In-Reply-To: <47593ba3-43c0-c7d3-2f4f-e649e21cb29a@linux.ibm.com> --Sx0zEr1v6Od5seHZBRbZigVRnETzvTDh3 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 05/02/2020 13.16, Janosch Frank wrote: > On 2/5/20 1:02 PM, Thomas Huth wrote: >> On 03/02/2020 14.19, Christian Borntraeger wrote: >>> From: Janosch Frank >>> >>> Now that we can't access guest memory anymore, we have a dedicated >>> sattelite block that's a bounce buffer for instruction data. >>> >>> We re-use the memop interface to copy the instruction data to / from >>> userspace. This lets us re-use a lot of QEMU code which used that >>> interface to make logical guest memory accesses which are not possible >>> anymore in protected mode anyway. >>> >>> Signed-off-by: Janosch Frank >>> --- >> [...] >>> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h >>> index eab741bc12c3..20969ce12096 100644 >>> --- a/include/uapi/linux/kvm.h >>> +++ b/include/uapi/linux/kvm.h >>> @@ -466,7 +466,7 @@ struct kvm_translation { >>> =09__u8 pad[5]; >>> }; >>> =20 >>> -/* for KVM_S390_MEM_OP */ >>> +/* for KVM_S390_MEM_OP and KVM_S390_SIDA_OP */ >>> struct kvm_s390_mem_op { >>> =09/* in */ >>> =09__u64 gaddr;=09=09/* the guest address */ >>> @@ -475,11 +475,17 @@ struct kvm_s390_mem_op { >>> =09__u32 op;=09=09/* type of operation */ >>> =09__u64 buf;=09=09/* buffer in userspace */ >>> =09__u8 ar;=09=09/* the access register number */ >>> -=09__u8 reserved[31];=09/* should be set to 0 */ >>> +=09__u8 reserved21[3];=09/* should be set to 0 */ >>> +=09__u32 offset;=09=09/* offset into the sida */ >>> +=09__u8 reserved28[24];=09/* should be set to 0 */ >>> }; >>> + >>> + >>> /* types for kvm_s390_mem_op->op */ >>> #define KVM_S390_MEMOP_LOGICAL_READ=090 >>> #define KVM_S390_MEMOP_LOGICAL_WRITE=091 >>> +#define KVM_S390_MEMOP_SIDA_READ=092 >>> +#define KVM_S390_MEMOP_SIDA_WRITE=093 >>> /* flags for kvm_s390_mem_op->flags */ >>> #define KVM_S390_MEMOP_F_CHECK_ONLY=09=09(1ULL << 0) >>> #define KVM_S390_MEMOP_F_INJECT_EXCEPTION=09(1ULL << 1) >>> @@ -1510,6 +1516,7 @@ struct kvm_pv_cmd { >>> /* Available with KVM_CAP_S390_PROTECTED */ >>> #define KVM_S390_PV_COMMAND=09=09_IOW(KVMIO, 0xc5, struct kvm_pv_cmd) >>> #define KVM_S390_PV_COMMAND_VCPU=09_IOW(KVMIO, 0xc6, struct kvm_pv_cmd= ) >>> +#define KVM_S390_SIDA_OP=09=09_IOW(KVMIO, 0xc7, struct kvm_s390_mem_op= ) >>> =20 >>> /* Secure Encrypted Virtualization command */ >>> enum sev_cmd_id { >>> >> >> Uh, why the mix of a new ioctl with the existing mem_op stuff? Could you >> please either properly integrate this into the MEM_OP ioctl (and e.g. >> use gaddr as offset for the new SIDA_READ and SIDA_WRITE subcodes), or >> completely separate it for a new ioctl, i.e. introduce a new struct for >> the new ioctl instead of recycling the struct kvm_s390_mem_op here? >> (and in case you ask me, I'd slightly prefer to integrate everything >> into MEM_OP instead of introducing a new ioctl here). >=20 > *cough* David and Christian didn't like the memop solution and it took > me a long time to get this to work properly in QEMU... I also don't like to re-use MEMOP_LOGICAL_READ and MEMOP_LOGICAL_WRITE for the SIDA like you've had it in RFC v1 ... but what's wrong with using KVM_S390_MEMOP_SIDA_READ and KVM_S390_MEMOP_SIDA_WRITE with the MEM_OP ioctl directly? Thomas --Sx0zEr1v6Od5seHZBRbZigVRnETzvTDh3-- --or1zbOiroipTYUWf2sALfNaXVNimODY4y Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEJ7iIR+7gJQEY8+q5LtnXdP5wLbUFAl469LYACgkQLtnXdP5w LbWeGQ/+I+dk7vvBkVJCjZysec1xQ3JoAgW8+gz8A5XkdkEHTzeLTdw+0MQvHck1 P2jenLXMDf/NbSZgkEjafW6gxQRIHzj1hjQQcsvv9Go+mOGi9mZPgkZRjJQHP26y 4JXapka1tZmRg+PHINs8lEgTUm4WFjRAe+P/DBfg8JQnLRh0RgUH5NHbdzXBq6bx QD3PR8pmQQy4PQRWHIhCjinUftaIX49kQGMfmo9LNAyHgIo11U97OSP7QqyUim12 Hgm4zyoZb2Sqdy7wSROZlcu4r2umCqWKlLiZLk4O5IRQ5kBfKbGvImHe/x1sCpii aU6V3+kkcTRNvI+F5EE6CeKrUZGbxb140iyT/NDmAZuCS3dfF6pLxS4ppDtiG0PO XYfNZHZUTlMhe6Pq7qPokCIqYjZU2Wx/Z1X8l8uaH1QGOs1Ppy1hlNr2z/THjH2k F2/QCn9+Q+NYGB2+4TH8Dz9x7OTrBVBKuh8cqOBNTjFwkxHx2qnERr6fWQ9eFIIk zAO5OjfPVSGpFMT9nkz4zDwOBJB4k3jKufaf+1zhAjpWJpjDoY5m3HvbGwrqBZgT tkyBMFvv4AewdDD9x+A5bJZNdN7iRqsBSUPpXgS3szz/68PY62KE0AZHqJuXUBoh ENe3Dc/y9SUQ5puAKfWTvIROdDXLfTfGscvGlW4JWERUMLrQGPY= =35yC -----END PGP SIGNATURE----- --or1zbOiroipTYUWf2sALfNaXVNimODY4y--