From nobody Fri Apr 3 02:58:26 2026 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 23C5D3FCB1C; Wed, 25 Mar 2026 17:13:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.156.1 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774458810; cv=none; b=e/VOcwNSjaoI77XZE77bkG8Mg5mtYS6V3idBxmsV3YibeRBemUILMK7vEQBrsGUw5yOzgw9a7y++rGkKUvzZl9mpPZL0QbqHbMsLgGcfyxofG6iK3uJtLAZw8cozCctyxjxUo9N1PbATXesIlTlweKDVgJbQqXcODgrk2zp385s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774458810; c=relaxed/simple; bh=TUIP8O/Lmpp9kp3YWRLfpndaoRJAsPL8xMtXjD9HidQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Bmdq4NAet7l422K5XSjcQ9EzR7wH03PtKurydg/VQ7WFHmwbaIR0DPjPKQudOnt1wdsPkeDJ70FRZzjzq3FaaV7ncVyGwic7NkSvcTUNwiZx3fMvF1k6BgQouoOKhGVf+W7TTCP1jgpiQNnw3pSLzIm/N7diwUHBoILVrBZ/V70= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=Zo2sRYaM; arc=none smtp.client-ip=148.163.156.1 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="Zo2sRYaM" Received: from pps.filterd (m0353729.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 62PBXv0i618716; Wed, 25 Mar 2026 17:13:18 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=pp1; bh=TPCEcBpmx9auzUSLj 7LRAxCfvlT/PVkVjehko+uH5/0=; b=Zo2sRYaMLREAmFKd/fVZ62T4UCJrspweE SCAqgjq20SpgAyYMhbwHnPW6CuYRu1za7S/VsqC8bFs1YVYl4EFtYZrYA+1yEV/d YjQRR3x2nngrG1bGZ5wM/rLYroWIYUHWHNIN6zFGSOTDcMKEm9hYjE0Dso4eFQl3 i6b/LdbHxccly7NByhbr8kitFhuPReeIqjVoPjBnWcCqvrX1VfAPqVz3xDujkexg iV7SuBU9XX+rEmV2429/7StaK5JKs6Tqsc8QZwWbUQ4e+3KNXReTA4Qyq8y3PDMP YDOB1Zbz/xv/mqplMYtpGciNATcEgxc9QgHFTuePYQLlJklQG6GJA== Received: from ppma13.dal12v.mail.ibm.com (dd.9e.1632.ip4.static.sl-reverse.com [50.22.158.221]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4d1kty1hkk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 25 Mar 2026 17:13:18 +0000 (GMT) Received: from pps.filterd (ppma13.dal12v.mail.ibm.com [127.0.0.1]) by ppma13.dal12v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id 62PG1BRd011824; Wed, 25 Mar 2026 17:13:17 GMT Received: from smtprelay07.fra02v.mail.ibm.com ([9.218.2.229]) by ppma13.dal12v.mail.ibm.com (PPS) with ESMTPS id 4d27vk79c2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 25 Mar 2026 17:13:17 +0000 Received: from smtpav03.fra02v.mail.ibm.com (smtpav03.fra02v.mail.ibm.com [10.20.54.102]) by smtprelay07.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 62PHDDvF44040588 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 25 Mar 2026 17:13:13 GMT Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 930F620040; Wed, 25 Mar 2026 17:13:13 +0000 (GMT) Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6674520043; Wed, 25 Mar 2026 17:13:13 +0000 (GMT) Received: from p-imbrenda.aag-de.ibm.com (unknown [9.52.223.175]) by smtpav03.fra02v.mail.ibm.com (Postfix) with ESMTP; Wed, 25 Mar 2026 17:13:13 +0000 (GMT) From: Claudio Imbrenda To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, borntraeger@de.ibm.com, frankja@linux.ibm.com, nrb@linux.ibm.com, seiden@linux.ibm.com, gra@linux.ibm.com, schlameuss@linux.ibm.com, hca@linux.ibm.com, david@kernel.org Subject: [PATCH v4 06/10] KVM: s390: vsie: Fix nested guest memory shadowing Date: Wed, 25 Mar 2026 18:13:07 +0100 Message-ID: <20260325171311.182210-7-imbrenda@linux.ibm.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260325171311.182210-1-imbrenda@linux.ibm.com> References: <20260325171311.182210-1-imbrenda@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=IqITsb/g c=1 sm=1 tr=0 ts=69c417ae cx=c_pps a=AfN7/Ok6k8XGzOShvHwTGQ==:117 a=AfN7/Ok6k8XGzOShvHwTGQ==:17 a=Yq5XynenixoA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=uAbxVGIbfxUO_5tXvNgY:22 a=VnNF1IyMAAAA:8 a=qWq0Kag4T7NBTqZ9-FgA:9 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMzI1MDEyMSBTYWx0ZWRfX4vcXyDNEObCC WzdaPZFdFP8L3oy0kOTJhtqPMRbKPYoC+Aw2X1EtyBs9LRsEENuVGnNZ33Lh891Im3O0mUCee2m dljhVAkMbsGnRhgMRz4bQ8/++A08pWVxHOH4hFJsiQ9cn9byUGWTDpju7FnaIMpY4tR0i8HK+w5 /zRKvpWrb5wi4WX6EGPJZPEEB6gKN9Y2Mkx03GbRAw0/8EIxxvBVCrE6s2aIDlejR30Q95RxNdR H6uuXbh3rBl649Ow1KrRlquOAL3U2hKVPYHjiyd5W5ddp2IXUFfFNfsWO5m/GulRXEiUwy2yIX8 cTsS8aJzGYBigsJJpImR7NVrPjtg/PMPA5dzMzsRWmidcGwhe2gditS6xk+7Oc8X+EEQ+pUVm8F cAXuTtk2OQqVMZZlLQFBGwNH2SlxY33Ie6VOLN39WTBeb8QJdIZ138XUq2bjswWQf09dg3qRM75 8ighdEX5U/GiZ2oulaw== X-Proofpoint-GUID: ysqmxU_ZB-yLVL-UzdrHjJTqTDwp_LGb X-Proofpoint-ORIG-GUID: ysqmxU_ZB-yLVL-UzdrHjJTqTDwp_LGb X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-03-25_05,2026-03-24_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 clxscore=1015 spamscore=0 impostorscore=0 suspectscore=0 phishscore=0 bulkscore=0 adultscore=0 priorityscore=1501 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2603050001 definitions=main-2603250121 Content-Type: text/plain; charset="utf-8" Fix _do_shadow_pte() to use the correct pointer (guest pte instead of nested guest) to set up the new pte. Add a check to return -EOPNOTSUPP if the mapping for the nested guest is writeable but the same page in the guest is only read-only. Signed-off-by: Claudio Imbrenda Fixes: e38c884df921 ("KVM: s390: Switch to new gmap") --- arch/s390/kvm/gaccess.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c index 8fd690255e1b..6655c214f2d7 100644 --- a/arch/s390/kvm/gaccess.c +++ b/arch/s390/kvm/gaccess.c @@ -1436,10 +1436,12 @@ static int _do_shadow_pte(struct gmap *sg, gpa_t ra= ddr, union pte *ptep_h, union =20 if (!pgste_get_trylock(ptep_h, &pgste)) return -EAGAIN; - newpte =3D _pte(f->pfn, f->writable, !p, 0); - newpte.s.d |=3D ptep->s.d; - newpte.s.sd |=3D ptep->s.sd; - newpte.h.p &=3D ptep->h.p; + newpte =3D _pte(f->pfn, f->writable, !p, ptep_h->s.s); + newpte.s.d |=3D ptep_h->s.d; + newpte.s.sd |=3D ptep_h->s.sd; + newpte.h.p &=3D ptep_h->h.p; + if (!newpte.h.p && !f->writable) + return -EOPNOTSUPP; pgste =3D _gmap_ptep_xchg(sg->parent, ptep_h, newpte, pgste, f->gfn, fals= e); pgste.vsie_notif =3D 1; pgste_set_unlock(ptep_h, pgste); @@ -1477,6 +1479,9 @@ static int _do_shadow_crste(struct gmap *sg, gpa_t ra= ddr, union crste *host, uni newcrste.h.p &=3D oldcrste.h.p; newcrste.s.fc1.vsie_notif =3D 1; newcrste.s.fc1.prefix_notif =3D oldcrste.s.fc1.prefix_notif; + newcrste.s.fc1.s =3D oldcrste.s.fc1.s; + if (!newcrste.h.p && !f->writable) + return -EOPNOTSUPP; } while (!_gmap_crstep_xchg_atomic(sg->parent, host, oldcrste, newcrste, = f->gfn, false)); =20 newcrste =3D _crste_fc1(f->pfn, oldcrste.h.tt, 0, !p); --=20 2.53.0