From f57ab9a01a36ef3454333251cc57e3a9948b17bf Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Fri, 17 Nov 2017 11:56:41 +0000 Subject: drivers: base: cacheinfo: fix cache type for non-architected system cache Commit dfea747d2aba ("drivers: base: cacheinfo: support DT overrides for cache properties") doesn't initialise the cache type if it's present only in DT and the architecture is not aware of it. They are unified system level cache which are generally transparent. This patch check if the cache type is set to NOCACHE but the DT node indicates that it's unified cache and sets the cache type accordingly. Fixes: dfea747d2aba ("drivers: base: cacheinfo: support DT overrides for cache properties") Reported-and-tested-by: Tan Xiaojun Cc: Greg Kroah-Hartman Signed-off-by: Sudeep Holla Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/base/cacheinfo.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index eb3af2739537..07532d83be0b 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -186,6 +186,11 @@ static void cache_associativity(struct cacheinfo *this_leaf) this_leaf->ways_of_associativity = (size / nr_sets) / line_size; } +static bool cache_node_is_unified(struct cacheinfo *this_leaf) +{ + return of_property_read_bool(this_leaf->of_node, "cache-unified"); +} + static void cache_of_override_properties(unsigned int cpu) { int index; @@ -194,6 +199,14 @@ static void cache_of_override_properties(unsigned int cpu) for (index = 0; index < cache_leaves(cpu); index++) { this_leaf = this_cpu_ci->info_list + index; + /* + * init_cache_level must setup the cache level correctly + * overriding the architecturally specified levels, so + * if type is NONE at this stage, it should be unified + */ + if (this_leaf->type == CACHE_TYPE_NOCACHE && + cache_node_is_unified(this_leaf)) + this_leaf->type = CACHE_TYPE_UNIFIED; cache_size(this_leaf); cache_get_line_size(this_leaf); cache_nr_sets(this_leaf); -- cgit v1.2.3 From 87590ce6e373d1a5401f6539f0c59ef92dd924a9 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sun, 7 Jan 2018 22:48:00 +0100 Subject: sysfs/cpu: Add vulnerability folder 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 Reviewed-by: Greg Kroah-Hartman Reviewed-by: Konrad Rzeszutek Wilk Cc: Peter Zijlstra Cc: Will Deacon Cc: Dave Hansen Cc: Linus Torvalds Cc: Borislav Petkov Cc: David Woodhouse Link: https://lkml.kernel.org/r/20180107214913.096657732@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(+) (limited to 'drivers/base') diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index f3d5817c4ef0..bd3a88e16d8b 100644 --- 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 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 +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 diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index 2f6614c9a229..37a71fd9043f 100644 --- 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 diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 321cd7b4d817..825964efda1d 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -501,10 +501,58 @@ static void __init cpu_dev_register_generic(void) #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(); } diff --git a/include/linux/cpu.h b/include/linux/cpu.h index 938ea8ae0ba4..c816e6f2730c 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -47,6 +47,13 @@ extern void cpu_remove_dev_attr(struct device_attribute *attr); 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, -- cgit v1.2.3