From nobody Mon Feb 9 00:42:48 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1569418074; cv=none; d=zoho.com; s=zohoarc; b=IX3ORxmZyrYpYsrl2SqlWPsT7L62qNWrOMmbaWZRUEB5ABDm3D+TriYitIfB2AkK2UP05GUJnLks8OZE0T373rmsj3JTqYhAsuVgoOo9tb9kCr5KK6AxIR5kCwca2l9qQprCpMgXn5H8fR/Z/jT5YEs6jagd9p9niT3QINDOLqo= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1569418074; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=La5XaJ9aiz++RZ/O4dQiLvktVcJ22FmrOaigmgGUKxM=; b=GyftMZyhB7DyFDs6E30p/x83GDbXcTqlkGtYVLW0mQOFCI7wrCOog/nR9Rt/NSj8g6Qvj4acjxWC7v7RstvkkgyhcAVKR+//pEe71Hku35RXvuk/rMmEaDxMt7naLpg5rpT2mQ+s4XYKi933lMLpVcBJD26Rl/YPQHSz9ILSnl0= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1569418074728617.3232427153199; Wed, 25 Sep 2019 06:27:54 -0700 (PDT) Received: from localhost ([::1]:50066 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iD7Ki-0000lS-MF for importer@patchew.org; Wed, 25 Sep 2019 09:27:52 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58780) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iD6mv-0006UU-2l for qemu-devel@nongnu.org; Wed, 25 Sep 2019 08:52:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iD6mt-00049N-Vj for qemu-devel@nongnu.org; Wed, 25 Sep 2019 08:52:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34566) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iD6mt-00048T-Ma; Wed, 25 Sep 2019 08:52:55 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D33576412E; Wed, 25 Sep 2019 12:52:54 +0000 (UTC) Received: from t460s.redhat.com (ovpn-117-14.ams2.redhat.com [10.36.117.14]) by smtp.corp.redhat.com (Postfix) with ESMTP id 12251600C8; Wed, 25 Sep 2019 12:52:52 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v2 4/7] s390x/mmu: Inject PGM_ADDRESSING on boguous table addresses Date: Wed, 25 Sep 2019 14:52:33 +0200 Message-Id: <20190925125236.4043-5-david@redhat.com> In-Reply-To: <20190925125236.4043-1-david@redhat.com> References: <20190925125236.4043-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Wed, 25 Sep 2019 12:52:54 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 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: Thomas Huth , Janosch Frank , David Hildenbrand , Cornelia Huck , Halil Pasic , Christian Borntraeger , qemu-s390x@nongnu.org, Richard Henderson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" Let's document how it works and inject PGM_ADDRESSING if reading of table entries fails. Signed-off-by: David Hildenbrand Reviewed-by: Thomas Huth --- target/s390x/mmu_helper.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/target/s390x/mmu_helper.c b/target/s390x/mmu_helper.c index f6ae444655..c9fde78614 100644 --- a/target/s390x/mmu_helper.c +++ b/target/s390x/mmu_helper.c @@ -93,6 +93,24 @@ target_ulong mmu_real2abs(CPUS390XState *env, target_ulo= ng raddr) return raddr; } =20 +static inline int read_table_entry(hwaddr gaddr, uint64_t *entry) +{ + /* + * According to the PoP, these table addresses are "unpredictably real + * or absolute". Also, "it is unpredictable whether the address wraps + * or an addressing exception is recognized". + * + * We treat them as absolute addresses and don't wrap them. + */ + if (unlikely(address_space_read(&address_space_memory, gaddr, + MEMTXATTRS_UNSPECIFIED, (uint8_t *)entry, sizeof(*entry))= !=3D + MEMTX_OK)) { + return -EFAULT; + } + *entry =3D be64_to_cpu(*entry); + return 0; +} + /* Decode page table entry (normal 4KB page) */ static int mmu_translate_pte(CPUS390XState *env, target_ulong vaddr, uint64_t asc, uint64_t pt_entry, @@ -118,7 +136,6 @@ static int mmu_translate_segment(CPUS390XState *env, ta= rget_ulong vaddr, target_ulong *raddr, int *flags, int rw, bool exc) { - CPUState *cs =3D env_cpu(env); uint64_t origin, offs, pt_entry; =20 if (st_entry & SEGMENT_ENTRY_RO) { @@ -134,7 +151,9 @@ static int mmu_translate_segment(CPUS390XState *env, ta= rget_ulong vaddr, /* Look up 4KB page entry */ origin =3D st_entry & SEGMENT_ENTRY_ORIGIN; offs =3D (vaddr & VADDR_PX) >> 9; - pt_entry =3D ldq_phys(cs->as, origin + offs); + if (read_table_entry(origin + offs, &pt_entry)) { + return PGM_ADDRESSING; + } return mmu_translate_pte(env, vaddr, asc, pt_entry, raddr, flags, rw, = exc); } =20 @@ -144,7 +163,6 @@ static int mmu_translate_region(CPUS390XState *env, tar= get_ulong vaddr, target_ulong *raddr, int *flags, int rw, bool exc) { - CPUState *cs =3D env_cpu(env); uint64_t origin, offs, new_entry; const int pchks[4] =3D { PGM_SEGMENT_TRANS, PGM_REG_THIRD_TRANS, @@ -154,7 +172,9 @@ static int mmu_translate_region(CPUS390XState *env, tar= get_ulong vaddr, origin =3D entry & REGION_ENTRY_ORIGIN; offs =3D (vaddr >> (17 + 11 * level / 4)) & 0x3ff8; =20 - new_entry =3D ldq_phys(cs->as, origin + offs); + if (read_table_entry(origin + offs, &new_entry)) { + return PGM_ADDRESSING; + } =20 if ((new_entry & REGION_ENTRY_INV) !=3D 0) { return pchks[level / 4]; --=20 2.21.0