From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Borislav Petkov <bp@alien8.de>,
David Woodhouse <dwmw@amazon.co.uk>,
Dave Hansen <dave.hansen@intel.com>,
Will Deacon <will.deacon@arm.com>
Subject: [patch V2 1/2] sysfs/cpu: Add vulnerability folder
Date: Sun, 07 Jan 2018 22:48:00 +0100 [thread overview]
Message-ID: <20180107214913.096657732@linutronix.de> (raw)
In-Reply-To: 20180107214759.387300853@linutronix.de
[-- Attachment #1: sysfs-cpu--Add-vulnerability-folder.patch --]
[-- Type: text/plain, Size: 4334 bytes --]
As the meltdown/spectre problem affects several CPU architectures, it makes
sense to have common way to express whether a system is affected by a
particular vulnerability or not. If affected the way to express the
mitigation should be common as well.
Create /sys/devices/system/cpu/vulnerabilities folder and files for
meltdown, spectre_v1 and spectre_v2.
Allow architectures to override the show function.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
Documentation/ABI/testing/sysfs-devices-system-cpu | 16 +++++++
drivers/base/Kconfig | 3 +
drivers/base/cpu.c | 48 +++++++++++++++++++++
include/linux/cpu.h | 7 +++
4 files changed, 74 insertions(+)
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -373,3 +373,19 @@ Contact: Linux kernel mailing list <linu
Description: information about CPUs heterogeneity.
cpu_capacity: capacity of cpu#.
+
+What: /sys/devices/system/cpu/vulnerabilities
+ /sys/devices/system/cpu/vulnerabilities/meltdown
+ /sys/devices/system/cpu/vulnerabilities/spectre_v1
+ /sys/devices/system/cpu/vulnerabilities/spectre_v2
+Date: Januar 2018
+Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description: Information about CPU vulnerabilities
+
+ The files are named after the code names of CPU
+ vulnerabilities. The output of those files reflects the
+ state of the CPUs in the system. Possible output values:
+
+ "Not affected" CPU is not affected by the vulnerability
+ "Vulnerable" CPU is affected and no mitigation in effect
+ "Mitigation: $M" CPU is affetcted and mitigation $M is in effect
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -235,6 +235,9 @@ config GENERIC_CPU_DEVICES
config GENERIC_CPU_AUTOPROBE
bool
+config GENERIC_CPU_VULNERABILITIES
+ bool
+
config SOC_BUS
bool
select GLOB
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -501,10 +501,58 @@ static void __init cpu_dev_register_gene
#endif
}
+#ifdef CONFIG_GENERIC_CPU_VULNERABILITIES
+
+ssize_t __weak cpu_show_meltdown(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "Not affected\n");
+}
+
+ssize_t __weak cpu_show_spectre_v1(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "Not affected\n");
+}
+
+ssize_t __weak cpu_show_spectre_v2(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "Not affected\n");
+}
+
+static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL);
+static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL);
+static DEVICE_ATTR(spectre_v2, 0444, cpu_show_spectre_v2, NULL);
+
+static struct attribute *cpu_root_vulnerabilities_attrs[] = {
+ &dev_attr_meltdown.attr,
+ &dev_attr_spectre_v1.attr,
+ &dev_attr_spectre_v2.attr,
+ NULL
+};
+
+static const struct attribute_group cpu_root_vulnerabilities_group = {
+ .name = "vulnerabilities",
+ .attrs = cpu_root_vulnerabilities_attrs,
+};
+
+static void __init cpu_register_vulnerabilities(void)
+{
+ if (sysfs_create_group(&cpu_subsys.dev_root->kobj,
+ &cpu_root_vulnerabilities_group))
+ pr_err("Unable to register CPU vulnerabilities\n");
+}
+
+#else
+static inline void cpu_register_vulnerabilities(void) { }
+#endif
+
void __init cpu_dev_init(void)
{
if (subsys_system_register(&cpu_subsys, cpu_root_attr_groups))
panic("Failed to register CPU subsystem");
cpu_dev_register_generic();
+ cpu_register_vulnerabilities();
}
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -47,6 +47,13 @@ extern void cpu_remove_dev_attr(struct d
extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
+extern ssize_t cpu_show_meltdown(struct device *dev,
+ struct device_attribute *attr, char *buf);
+extern ssize_t cpu_show_spectre_v1(struct device *dev,
+ struct device_attribute *attr, char *buf);
+extern ssize_t cpu_show_spectre_v2(struct device *dev,
+ struct device_attribute *attr, char *buf);
+
extern __printf(4, 5)
struct device *cpu_device_create(struct device *parent, void *drvdata,
const struct attribute_group **groups,
next prev parent reply other threads:[~2018-01-07 21:49 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-07 21:47 [patch V2 0/2] sysfs/cpu: Implement generic vulnerabilites directory Thomas Gleixner
2018-01-07 21:48 ` Thomas Gleixner [this message]
2018-01-07 22:14 ` [patch V2 1/2] sysfs/cpu: Add vulnerability folder Konrad Rzeszutek Wilk
2018-01-08 6:53 ` Greg Kroah-Hartman
2018-01-08 7:29 ` Dominik Brodowski
2018-01-08 7:33 ` Thomas Gleixner
2018-01-08 10:16 ` [tip:x86/pti] " tip-bot for Thomas Gleixner
2018-01-26 16:23 ` [patch V2 1/2] " Andrea Arcangeli
2018-01-26 16:35 ` Greg Kroah-Hartman
2018-01-29 5:30 ` Jon Masters
2018-01-07 21:48 ` [patch V2 2/2] x86/cpu: Implement CPU vulnerabilites sysfs functions Thomas Gleixner
2018-01-07 22:14 ` Konrad Rzeszutek Wilk
2018-01-08 6:54 ` Greg Kroah-Hartman
2018-01-08 10:17 ` [tip:x86/pti] " tip-bot for Thomas Gleixner
2018-01-07 22:22 [patch V2 1/2] sysfs/cpu: Add vulnerability folder Alexey Dobriyan
2018-01-08 3:50 ` Konrad Rzeszutek Wilk
2018-01-08 5:35 ` Alexey Dobriyan
2018-01-08 9:36 ` Thomas Gleixner
2018-01-08 10:30 ` Alexey Dobriyan
2018-01-08 11:54 ` Alan Cox
2018-01-08 18:04 ` Alexey Dobriyan
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