From patchwork Mon May 21 04:21:07 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ravi Bangoria X-Patchwork-Id: 917330 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40q5Nh2TMpz9s3D for ; Mon, 21 May 2018 14:27:48 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 40q5Nh0zj0zF0jD for ; Mon, 21 May 2018 14:27:48 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=linux.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=ravi.bangoria@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com 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 lists.ozlabs.org (Postfix) with ESMTPS id 40q5FT6MYzzF0fW for ; Mon, 21 May 2018 14:21:33 +1000 (AEST) Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w4L4J4DS047965 for ; Mon, 21 May 2018 00:21:31 -0400 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0a-001b2d01.pphosted.com with ESMTP id 2j3jqk7e23-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 21 May 2018 00:21:31 -0400 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 21 May 2018 05:21:24 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w4L4LNmL6816032 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 21 May 2018 04:21:23 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id DD841AE04D; Mon, 21 May 2018 05:10:38 +0100 (BST) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 60F65AE045; Mon, 21 May 2018 05:10:36 +0100 (BST) Received: from bangoria.in.ibm.com (unknown [9.109.219.149]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 21 May 2018 05:10:36 +0100 (BST) From: Ravi Bangoria To: mpe@ellerman.id.au, mikey@neuling.org Subject: [PATCH 2/3] powerpc/sstep: Fix kernel crash if VSX is not present Date: Mon, 21 May 2018 09:51:07 +0530 X-Mailer: git-send-email 2.14.3 In-Reply-To: <20180521042108.8318-1-ravi.bangoria@linux.ibm.com> References: <20180521042108.8318-1-ravi.bangoria@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18052104-0008-0000-0000-000004F8A56F X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18052104-0009-0000-0000-00001E8D2B40 Message-Id: <20180521042108.8318-3-ravi.bangoria@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-05-21_01:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1805210051 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: sandipan@linux.vnet.ibm.com, Ravi Bangoria , linux-kernel@vger.kernel.org, matthew.brown.dev@gmail.com, paulus@samba.org, anton@samba.org, naveen.n.rao@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org, cyrilbur@gmail.com Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" emulate_step() is not checking runtime VSX feature flag before emulating an instruction. This is causing kernel crash when kernel is compiled with CONFIG_VSX=y but running on a machine where VSX is not supported or disabled. Ex, while running emulate_step tests on P6 machine: Oops: Exception in kernel mode, sig: 4 [#1] NIP [c000000000095c24] .load_vsrn+0x28/0x54 LR [c000000000094bdc] .emulate_loadstore+0x167c/0x17b0 Call Trace: 0x40fe240c7ae147ae (unreliable) .emulate_loadstore+0x167c/0x17b0 .emulate_step+0x25c/0x5bc .test_lxvd2x_stxvd2x+0x64/0x154 .test_emulate_step+0x38/0x4c .do_one_initcall+0x5c/0x2c0 .kernel_init_freeable+0x314/0x4cc .kernel_init+0x24/0x160 .ret_from_kernel_thread+0x58/0xb4 With fix: emulate_step_test: lxvd2x : FAIL emulate_step_test: stxvd2x : FAIL Fixes: https://github.com/linuxppc/linux/issues/148 Reported-by: Michael Ellerman Signed-off-by: Ravi Bangoria --- arch/powerpc/lib/sstep.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index db6bba259d91..23b7ddf04521 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -2544,6 +2544,15 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs, #endif /* __powerpc64__ */ } + +#ifdef CONFIG_VSX + if ((GETTYPE(op->type) == LOAD_VSX || + GETTYPE(op->type) == STORE_VSX) && + !cpu_has_feature(CPU_FTR_VSX)) { + return -1; + } +#endif /* CONFIG_VSX */ + return 0; logical_done: