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=-9.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 CD366C2D0E4 for ; Tue, 17 Nov 2020 14:18:29 +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 2BFF4221F8 for ; Tue, 17 Nov 2020 14:18:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="O7T84opM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2BFF4221F8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:40096 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kf1oS-0003po-0B for qemu-devel@archiver.kernel.org; Tue, 17 Nov 2020 09:18:28 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:60118) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kf1kK-0007gd-Tm for qemu-devel@nongnu.org; Tue, 17 Nov 2020 09:14:13 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:35658) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kf1kI-0002Np-SK for qemu-devel@nongnu.org; Tue, 17 Nov 2020 09:14:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1605622450; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WxlETIixCnXncrzehMeusPU6L4CxgBvniAps6EzuUPs=; b=O7T84opMZ4Q6NkEH6UekcKZFA1HARVnrM86Lnemu2aAFqlCD/NGJQ+moUrZuPIswKZD4eU 99u/PosVcMwq4dIvWcC4r4wV6bbk4wl9WC2iGGX7N5wVjsZgFZLJK1GFsr5n/hvSiJJY/7 aX4wnAz60zqFeS4nXq1iu5LyWNZybyA= 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-211-_VB4l4kjMx--v-Geg_GkBQ-1; Tue, 17 Nov 2020 09:13:53 -0500 X-MC-Unique: _VB4l4kjMx--v-Geg_GkBQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B69C0800050; Tue, 17 Nov 2020 14:13:51 +0000 (UTC) Received: from gondolin (ovpn-113-115.ams2.redhat.com [10.36.113.115]) by smtp.corp.redhat.com (Postfix) with ESMTP id 567A018439; Tue, 17 Nov 2020 14:13:43 +0000 (UTC) Date: Tue, 17 Nov 2020 15:13:40 +0100 From: Cornelia Huck To: Matthew Rosato Subject: Re: [RFC PATCH-for-5.2] hw/s390x/pci: Fix endianness issue Message-ID: <20201117151340.539d55b2.cohuck@redhat.com> In-Reply-To: References: <20201117120115.1234994-1-philmd@redhat.com> <20201117143117.4b05db78.cohuck@redhat.com> Organization: Red Hat GmbH MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=cohuck@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=216.205.24.124; envelope-from=cohuck@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/11/17 01:18:45 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] 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_H4=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Thomas Huth , Pierre Morel , David Hildenbrand , qemu-s390x , Richard Henderson , QEMU Developers , Halil Pasic , Christian Borntraeger , Alex Williamson , Philippe =?UTF-8?B?TWF0aGlldS1EYXVkw6k=?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, 17 Nov 2020 09:02:37 -0500 Matthew Rosato wrote: > On 11/17/20 8:31 AM, Cornelia Huck wrote: > > On Tue, 17 Nov 2020 14:23:57 +0100 > > Pierre Morel wrote: > > =20 > >> On 11/17/20 2:00 PM, Peter Maydell wrote: =20 > >>> On Tue, 17 Nov 2020 at 12:03, Philippe Mathieu-Daud=C3=A9 wrote: =20 > >>>> > >>>> Fix an endianness issue reported by Cornelia: > >>>> =20 > >>>>> s390x tcg guest on x86, virtio-pci devices are not detected. The > >>>>> relevant feature bits are visible to the guest. Same breakage with > >>>>> different guest kernels. > >>>>> KVM guests and s390x tcg guests on s390x are fine. =20 > >>>> > >>>> Fixes: 28dc86a0729 ("s390x/pci: use a PCI Group structure") > >>>> Reported-by: Cornelia Huck > >>>> Signed-off-by: Philippe Mathieu-Daud=C3=A9 > >>>> --- > >>>> RFC because review-only patch, untested > >>>> --- > >>>> hw/s390x/s390-pci-inst.c | 2 +- > >>>> 1 file changed, 1 insertion(+), 1 deletion(-) > >>>> > >>>> diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c > >>>> index 58cd041d17f..cfb54b4d8ec 100644 > >>>> --- a/hw/s390x/s390-pci-inst.c > >>>> +++ b/hw/s390x/s390-pci-inst.c > >>>> @@ -305,7 +305,7 @@ int clp_service_call(S390CPU *cpu, uint8_t r2, u= intptr_t ra) > >>>> ClpReqQueryPciGrp *reqgrp =3D (ClpReqQueryPciGrp *)reqh; > >>>> S390PCIGroup *group; > >>>> > >>>> - group =3D s390_group_find(reqgrp->g); > >>>> + group =3D s390_group_find(ldl_p(&reqgrp->g)); =20 > >>> > >>> 'g' in the ClpReqQueryPciGrp struct is a uint32_t, so > >>> adding the ldl_p() will have no effect unless (a) the > >>> structure is not 4-aligned and (b) the host will fault on > >>> unaligned accesses, which isn't the case for x86 hosts. > >>> > >>> Q: is this struct really in host order, or should we > >>> be using ldl_le_p() or ldl_be_p() and friends here and > >>> elsewhere? > >>> > >>> thanks > >>> -- PMM > >>> =20 > >> > >> Hi, I think we better modify the structure here, g should be a byte. > >> > >> Connie, can you please try this if it resolves the issue? > >> > >> diff --git a/hw/s390x/s390-pci-inst.h b/hw/s390x/s390-pci-inst.h > >> index fa3bf8b5aa..641d19c815 100644 > >> --- a/hw/s390x/s390-pci-inst.h > >> +++ b/hw/s390x/s390-pci-inst.h > >> @@ -146,7 +146,8 @@ typedef struct ClpReqQueryPciGrp { > >> uint32_t fmt; > >> uint64_t reserved1; > >> #define CLP_REQ_QPCIG_MASK_PFGID 0xff > >> - uint32_t g; > >> + uint32_t g0 :24; > >> + uint32_t g :8; > >> uint32_t reserved2; > >> uint64_t reserved3; > >> } QEMU_PACKED ClpReqQueryPciGrp; > >> =20 > >=20 > > No, same crash... I fear there are more things broken wrt endianness. > > =20 >=20 > Sorry, just getting online now, looking at the code.... Are the 2=20 > memcpy calls added in 9670ee75 and 28dc86a0 the issue? Won't they just= =20 > present the Q PCI FN / Q PCI FN GRP results in host endianness? >=20 I just re-added some st?_p operations in set_pbdev_info and that fixes at least the crash I was seeing with Phil's patch applied. Still, no pci functions get detected, so that's not enough. Those memcpy calls look like a possible culprit.