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=-6.9 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 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 4613DC43603 for ; Tue, 17 Dec 2019 15:07:36 +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 10C8B2146E for ; Tue, 17 Dec 2019 15:07:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OwkiPiFZ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 10C8B2146E 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]:41644 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ihERj-0004IU-7i for qemu-devel@archiver.kernel.org; Tue, 17 Dec 2019 10:07:35 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:41948) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ihER2-0003sG-9n for qemu-devel@nongnu.org; Tue, 17 Dec 2019 10:06:53 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ihER1-0005hE-6j for qemu-devel@nongnu.org; Tue, 17 Dec 2019 10:06:52 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:27255 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ihER1-0005gr-3d for qemu-devel@nongnu.org; Tue, 17 Dec 2019 10:06:51 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576595210; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=w1NTDSSbVt0UV5fVN8/Oq8z3wDEy4qKOZPHKybkPFO4=; b=OwkiPiFZfEXrfrLVoUIY5l7+D26gbPRxfmKm5yVF03bIQB6dlFQ3+lGwSku8ZkDbJfeXcc S61+cYPYZzcnJQtnuRt2S/+zMwOb84QhLN+8CZsTU8yZdNyKXr0G/JdKqZoBo5HnNQcmlZ 1DIwfdsoEAy4tL30zomiPFbeAU58514= 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-165-Rgi8LtcLPNaM-I3MQO1g1g-1; Tue, 17 Dec 2019 10:06:47 -0500 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4458E800D4E; Tue, 17 Dec 2019 15:06:46 +0000 (UTC) Received: from thuth.com (ovpn-116-149.ams2.redhat.com [10.36.116.149]) by smtp.corp.redhat.com (Postfix) with ESMTP id 05C1610016DA; Tue, 17 Dec 2019 15:06:44 +0000 (UTC) From: Thomas Huth To: Cornelia Huck , qemu-devel@nongnu.org Subject: [PATCH] tests/boot-sector: Fix the bad s390x assembler code Date: Tue, 17 Dec 2019 16:06:42 +0100 Message-Id: <20191217150642.27946-1-thuth@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-MC-Unique: Rgi8LtcLPNaM-I3MQO1g1g-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=US-ASCII 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: 207.211.31.120 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: qemu-s390x@nongnu.org, Janosch Frank Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" There are currently two bugs in s390x_code[]: First, the initial jump uses the wrong offset, so it was jumping to 0x1014 instead of 0x1010. Second, LHI only loads the lower 32-bit of the register. Everything worked fine as long as the s390-ccw bios code was jumping here with r3 containing zeroes in the uppermost 48 bit - which just happened to be the case so far by accident. But we can not rely on this fact, and indeed one of the recent suggested patches to jump2ipl.c cause the newer GCCs to put different values into r3. In that case the code from s390x_code[] crashes very ungracefully. Thus let's make sure to jump to the right instruction, and use LGHI instead of LHI to make sure that we always zero out the upper bits of the register. Signed-off-by: Thomas Huth --- tests/boot-sector.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tests/boot-sector.c b/tests/boot-sector.c index 7824286b9a..9e66c6d013 100644 --- a/tests/boot-sector.c +++ b/tests/boot-sector.c @@ -75,11 +75,11 @@ static const uint8_t s390x_psw_and_magic[] =3D { 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40 /* in the s390-ccw bi= os */ }; static const uint8_t s390x_code[] =3D { - 0xa7, 0xf4, 0x00, 0x0a, /* j 0x10010 */ + 0xa7, 0xf4, 0x00, 0x08, /* j 0x10010 */ 0x00, 0x00, 0x00, 0x00, 'S', '3', '9', '0', 'E', 'P', 0x00, 0x01, - 0xa7, 0x38, HIGH(SIGNATURE_ADDR), LOW(SIGNATURE_ADDR), /* lhi r3,0x7c1= 0 */ + 0xa7, 0x39, HIGH(SIGNATURE_ADDR), LOW(SIGNATURE_ADDR), /* lghi r3,0x7c= 10 */ 0xa7, 0x48, LOW(SIGNATURE), HIGH(SIGNATURE), /* lhi r4,0xadd= e */ 0x40, 0x40, 0x30, 0x00, /* sth r4,0(r3)= */ 0xa7, 0xf4, 0xff, 0xfa /* j 0x10010 */ --=20 2.18.1