From patchwork Tue Dec 18 09:26:49 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Janosch Frank X-Patchwork-Id: 10735251 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E82AA6C2 for ; Tue, 18 Dec 2018 09:29:25 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D908D29AAE for ; Tue, 18 Dec 2018 09:29:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CDB1229B59; Tue, 18 Dec 2018 09:29:25 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7781D29AAE for ; Tue, 18 Dec 2018 09:29:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726582AbeLRJ3Y (ORCPT ); Tue, 18 Dec 2018 04:29:24 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:51016 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726593AbeLRJ3X (ORCPT ); Tue, 18 Dec 2018 04:29:23 -0500 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id wBI9SY6Q098157 for ; Tue, 18 Dec 2018 04:29:22 -0500 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0b-001b2d01.pphosted.com with ESMTP id 2peuumxyyd-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 18 Dec 2018 04:29:22 -0500 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 18 Dec 2018 09:29:20 -0000 Received: from b06cxnps3075.portsmouth.uk.ibm.com (9.149.109.195) by e06smtp05.uk.ibm.com (192.168.101.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Tue, 18 Dec 2018 09:29:18 -0000 Received: from d06av24.portsmouth.uk.ibm.com (d06av24.portsmouth.uk.ibm.com [9.149.105.60]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id wBI9TH9W57803000 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 18 Dec 2018 09:29:17 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0F4BA42049; Tue, 18 Dec 2018 09:29:17 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D325A42042; Tue, 18 Dec 2018 09:29:16 +0000 (GMT) Received: from s38lp20.lnxne.boe (unknown [9.152.224.44]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 18 Dec 2018 09:29:16 +0000 (GMT) From: Janosch Frank To: kvm@vger.kernel.org Cc: linux-s390@vger.kernel.org, david@redhat.com, thuth@redhat.com Subject: [kvm-unit-tests PATCH v3 05/13] s390x: Add BSS clearing for non ELF boot Date: Tue, 18 Dec 2018 10:26:49 +0100 X-Mailer: git-send-email 2.14.3 In-Reply-To: <20181218092657.46466-1-frankja@linux.ibm.com> References: <20181218092657.46466-1-frankja@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18121809-0020-0000-0000-000002F93063 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18121809-0021-0000-0000-000021493265 Message-Id: <20181218092657.46466-6-frankja@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-12-18_04:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=930 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1812180085 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When doing an IPL normal the memory will not be zeroed and hence the BSS section can have any value. We need to clear it by ourselves. Signed-off-by: Janosch Frank Reviewed-by: Thomas Huth --- s390x/cstart64.S | 21 ++++++++++++++++++++- s390x/flat.lds | 2 ++ 2 files changed, 22 insertions(+), 1 deletion(-) diff --git a/s390x/cstart64.S b/s390x/cstart64.S index 7886f35..aba11f4 100644 --- a/s390x/cstart64.S +++ b/s390x/cstart64.S @@ -37,6 +37,22 @@ start: /* setup initial PSW mask + control registers*/ larl %r1, initial_psw lpswe 0(%r1) +init_clear_bss: + larl %r2, __bss_start + larl %r3, __bss_end + slgr %r3, %r2 # Get sizeof bss + aghi %r3,-1 + srlg %r4,%r3,8 # Calc number of 256 byte chunks + ltgr %r4,%r4 + lgr %r1,%r2 + jz remainder # If none, clear remaining bytes +loop: + xc 0(256,%r1), 0(%r1) # Clear 256 byte chunks via xor + la %r1, 256(%r1) + brctg %r4, loop +remainder: + larl %r2, memsetxc + ex %r3, 0(%r2) init_psw_cont: /* setup pgm interrupt handler */ larl %r1, pgm_int_psw @@ -69,6 +85,9 @@ init_psw_cont: /* call exit() */ j exit +memsetxc: + xc 0(1,%r1),0(%r1) + .macro SAVE_REGS /* save grs 0-15 */ stmg %r0, %r15, GEN_LC_SW_INT_GRS @@ -157,7 +176,7 @@ svc_int: .align 8 initial_psw: - .quad 0x0000000180000000, init_psw_cont + .quad 0x0000000180000000, init_clear_bss pgm_int_psw: .quad 0x0000000180000000, pgm_int ext_int_psw: diff --git a/s390x/flat.lds b/s390x/flat.lds index 977af7c..403d967 100644 --- a/s390x/flat.lds +++ b/s390x/flat.lds @@ -40,7 +40,9 @@ SECTIONS . = ALIGN(16); .rodata : { *(.rodata) *(.rodata.*) } . = ALIGN(16); + __bss_start = .; .bss : { *(.bss) } + __bss_end = .; . = ALIGN(64K); edata = .; . += 64K;