From patchwork Fri Jul 17 14:38:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Athira Rajeev X-Patchwork-Id: 11670479 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 90B9413B6 for ; Fri, 17 Jul 2020 14:39:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8309422BF3 for ; Fri, 17 Jul 2020 14:39:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728056AbgGQOjT (ORCPT ); Fri, 17 Jul 2020 10:39:19 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:63846 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728014AbgGQOjS (ORCPT ); Fri, 17 Jul 2020 10:39:18 -0400 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 06HEWqU2141015; Fri, 17 Jul 2020 10:39:06 -0400 Received: from ppma03fra.de.ibm.com (6b.4a.5195.ip4.static.sl-reverse.com [149.81.74.107]) by mx0a-001b2d01.pphosted.com with ESMTP id 32b9ag0kw5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 10:39:05 -0400 Received: from pps.filterd (ppma03fra.de.ibm.com [127.0.0.1]) by ppma03fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 06HEU73e024878; Fri, 17 Jul 2020 14:39:03 GMT Received: from b06cxnps4076.portsmouth.uk.ibm.com (d06relay13.portsmouth.uk.ibm.com [9.149.109.198]) by ppma03fra.de.ibm.com with ESMTP id 327527kf7f-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 14:39:03 +0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 06HEd1gN57802966 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Jul 2020 14:39:01 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id DBF534C044; Fri, 17 Jul 2020 14:39:00 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 45A6A4C058; Fri, 17 Jul 2020 14:38:58 +0000 (GMT) Received: from localhost.localdomain.localdomain (unknown [9.77.207.73]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 17 Jul 2020 14:38:58 +0000 (GMT) From: Athira Rajeev To: mpe@ellerman.id.au Cc: linuxppc-dev@lists.ozlabs.org, maddy@linux.vnet.ibm.com, mikey@neuling.org, kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, ego@linux.vnet.ibm.com, svaidyan@in.ibm.com, acme@kernel.org, jolsa@kernel.org Subject: [v3 09/15] powerpc/perf: Ignore the BHRB kernel address filtering for P10 Date: Fri, 17 Jul 2020 10:38:21 -0400 Message-Id: <1594996707-3727-10-git-send-email-atrajeev@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1594996707-3727-1-git-send-email-atrajeev@linux.vnet.ibm.com> References: <1594996707-3727-1-git-send-email-atrajeev@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-07-17_06:2020-07-17,2020-07-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 priorityscore=1501 spamscore=0 mlxscore=0 phishscore=0 suspectscore=1 lowpriorityscore=0 impostorscore=0 clxscore=1015 malwarescore=0 mlxlogscore=703 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007170108 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org commit bb19af816025 ("powerpc/perf: Prevent kernel address leak to userspace via BHRB buffer") added a check in bhrb_read() to filter the kernel address from BHRB buffer. This patch modified it to avoid that check for PowerISA v3.1 based processors, since PowerISA v3.1 allows only MSR[PR]=1 address to be written to BHRB buffer. Signed-off-by: Athira Rajeev --- arch/powerpc/perf/core-book3s.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index 0ffb757d..bd125fe 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -469,8 +469,11 @@ static void power_pmu_bhrb_read(struct perf_event *event, struct cpu_hw_events * * addresses at this point. Check the privileges before * exporting it to userspace (avoid exposure of regions * where we could have speculative execution) + * Incase of ISA v3.1, BHRB will capture only user-space + * addresses, hence include a check before filtering code */ - if (is_kernel_addr(addr) && perf_allow_kernel(&event->attr) != 0) + if (!(ppmu->flags & PPMU_ARCH_310S) && + is_kernel_addr(addr) && perf_allow_kernel(&event->attr) != 0) continue; /* Branches are read most recent first (ie. mfbhrb 0 is