All of lore.kernel.org
 help / color / mirror / Atom feed
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, stable@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Subject: [PATCH 17/19] s390: add sysfs attributes for spectre
Date: Fri, 27 Apr 2018 07:36:55 +0200	[thread overview]
Message-ID: <20180427053657.56944-18-schwidefsky@de.ibm.com> (raw)
In-Reply-To: <20180427053657.56944-1-schwidefsky@de.ibm.com>

[ 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 <schwidefsky@de.ibm.com>
---
 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 fbb8fca6f9c2..1c4a595e8224 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -118,6 +118,7 @@ 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 <linux/module.h>
+#include <linux/device.h>
 #include <asm/facility.h>
 #include <asm/nospec-branch.h>
 
@@ -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

  parent reply	other threads:[~2018-04-27  5:37 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-27  5:36 [PATCH 00/19] s390 spectre mititgation for 4.9 Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 01/19] s390: introduce CPU alternatives Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 02/19] s390: enable CPU alternatives unconditionally Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 03/19] KVM: s390: wire up bpb feature Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 04/19] s390: scrub registers on kernel entry and KVM exit Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 05/19] s390: add optimized array_index_mask_nospec Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 06/19] s390/alternative: use a copy of the facility bit mask Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 07/19] s390: add options to change branch prediction behaviour for the kernel Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 08/19] s390: run user space and KVM guests with modified branch prediction Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 09/19] s390: introduce execute-trampolines for branches Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 10/19] KVM: s390: force bp isolation for VSIE Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 11/19] s390: Replace IS_ENABLED(EXPOLINE_*) with IS_ENABLED(CONFIG_EXPOLINE_*) Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 12/19] s390: do not bypass BPENTER for interrupt system calls Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 13/19] s390/entry.S: fix spurious zeroing of r0 Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 14/19] s390: move nobp parameter functions to nospec-branch.c Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 15/19] s390: add automatic detection of the spectre defense Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 16/19] s390: report spectre mitigation via syslog Martin Schwidefsky
2018-04-27  5:36 ` Martin Schwidefsky [this message]
2018-04-27  5:36 ` [PATCH 18/19] s390: correct nospec auto detection init order Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 19/19] s390: correct module section names for expoline code revert Martin Schwidefsky
2018-04-27 10:11 ` [PATCH 00/19] s390 spectre mititgation for 4.9 Greg Kroah-Hartman
  -- strict thread matches above, loose matches on Subject: below --
2018-04-27  5:36 [PATCH 00/19] s390 spectre mititgation for 4.14 Martin Schwidefsky
2018-04-27  5:36 ` [PATCH 17/19] s390: add sysfs attributes for spectre Martin Schwidefsky

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180427053657.56944-18-schwidefsky@de.ibm.com \
    --to=schwidefsky@de.ibm.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=stable@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.