From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:60966 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757436AbeD0FhI (ORCPT ); Fri, 27 Apr 2018 01:37:08 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w3R5YeBg035836 for ; Fri, 27 Apr 2018 01:37:07 -0400 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0b-001b2d01.pphosted.com with ESMTP id 2hkwmwgds6-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 27 Apr 2018 01:37:07 -0400 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 27 Apr 2018 06:37:05 +0100 From: Martin Schwidefsky To: Greg Kroah-Hartman , stable@vger.kernel.org Cc: Martin Schwidefsky Subject: [PATCH 16/18] s390: add sysfs attributes for spectre Date: Fri, 27 Apr 2018 07:37:00 +0200 In-Reply-To: <20180427053702.57047-1-schwidefsky@de.ibm.com> References: <20180427053702.57047-1-schwidefsky@de.ibm.com> Message-Id: <20180427053702.57047-17-schwidefsky@de.ibm.com> Sender: stable-owner@vger.kernel.org List-ID: [ Upstream commit d424986f1d6b16079b3231db0314923f4f8deed1 ] Set CONFIG_GENERIC_CPU_VULNERABILITIES and provide the two functions cpu_show_spectre_v1 and cpu_show_spectre_v2 to report the spectre mitigations. Signed-off-by: Martin Schwidefsky --- arch/s390/Kconfig | 1 + arch/s390/kernel/nospec-branch.c | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+) diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 75c4a78d2e1c..9bdaeb38a768 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -111,6 +111,7 @@ config S390 select GENERIC_CLOCKEVENTS select GENERIC_CPU_AUTOPROBE select GENERIC_CPU_DEVICES if !SMP + select GENERIC_CPU_VULNERABILITIES select GENERIC_FIND_FIRST_BIT select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL diff --git a/arch/s390/kernel/nospec-branch.c b/arch/s390/kernel/nospec-branch.c index 7387ebace891..73c06d42792d 100644 --- a/arch/s390/kernel/nospec-branch.c +++ b/arch/s390/kernel/nospec-branch.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include +#include #include #include @@ -43,6 +44,24 @@ static int __init nospec_report(void) } arch_initcall(nospec_report); +#ifdef CONFIG_SYSFS +ssize_t cpu_show_spectre_v1(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "Mitigation: __user pointer sanitization\n"); +} + +ssize_t cpu_show_spectre_v2(struct device *dev, + struct device_attribute *attr, char *buf) +{ + if (IS_ENABLED(CC_USING_EXPOLINE) && !nospec_disable) + return sprintf(buf, "Mitigation: execute trampolines\n"); + if (__test_facility(82, S390_lowcore.alt_stfle_fac_list)) + return sprintf(buf, "Mitigation: limited branch prediction.\n"); + return sprintf(buf, "Vulnerable\n"); +} +#endif + #ifdef CONFIG_EXPOLINE int nospec_disable = IS_ENABLED(CONFIG_EXPOLINE_OFF); -- 2.13.5