diff options
Diffstat (limited to 'drivers/base/cpu.c')
| -rw-r--r-- | drivers/base/cpu.c | 245 |
1 files changed, 156 insertions, 89 deletions
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 4c98849577d4..c6c57b6f61c6 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -19,13 +19,14 @@ #include <linux/cpufeature.h> #include <linux/tick.h> #include <linux/pm_qos.h> +#include <linux/delay.h> #include <linux/sched/isolation.h> #include "base.h" static DEFINE_PER_CPU(struct device *, cpu_sys_devices); -static int cpu_subsys_match(struct device *dev, struct device_driver *drv) +static int cpu_subsys_match(struct device *dev, const struct device_driver *drv) { /* ACPI style match is the only one that may succeed. */ if (acpi_driver_match_device(dev, drv)) @@ -50,12 +51,30 @@ static int cpu_subsys_online(struct device *dev) int cpuid = dev->id; int from_nid, to_nid; int ret; + int retries = 0; from_nid = cpu_to_node(cpuid); if (from_nid == NUMA_NO_NODE) return -ENODEV; +retry: ret = cpu_device_up(dev); + + /* + * If -EBUSY is returned, it is likely that hotplug is temporarily + * disabled when cpu_hotplug_disable() was called. This condition is + * transient. So we retry after waiting for an exponentially + * increasing delay up to a total of at least 620ms as some PCI + * device initialization can take quite a while. + */ + if (ret == -EBUSY) { + retries++; + if (retries > 5) + return ret; + msleep(10 * (1 << retries)); + goto retry; + } + /* * When hot adding memory to memoryless node and enabling a cpu * on the node, node number of the cpu may internally change. @@ -76,6 +95,7 @@ void unregister_cpu(struct cpu *cpu) { int logical_cpu = cpu->dev.id; + set_cpu_enabled(logical_cpu, false); unregister_cpu_under_node(logical_cpu, cpu_to_node(logical_cpu)); device_unregister(&cpu->dev); @@ -125,18 +145,7 @@ static DEVICE_ATTR(release, S_IWUSR, NULL, cpu_release_store); #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */ #endif /* CONFIG_HOTPLUG_CPU */ -struct bus_type cpu_subsys = { - .name = "cpu", - .dev_name = "cpu", - .match = cpu_subsys_match, -#ifdef CONFIG_HOTPLUG_CPU - .online = cpu_subsys_online, - .offline = cpu_subsys_offline, -#endif -}; -EXPORT_SYMBOL_GPL(cpu_subsys); - -#ifdef CONFIG_KEXEC +#ifdef CONFIG_CRASH_DUMP #include <linux/kexec.h> static ssize_t crash_notes_show(struct device *dev, @@ -181,14 +190,14 @@ static const struct attribute_group crash_note_cpu_attr_group = { #endif static const struct attribute_group *common_cpu_attr_groups[] = { -#ifdef CONFIG_KEXEC +#ifdef CONFIG_CRASH_DUMP &crash_note_cpu_attr_group, #endif NULL }; static const struct attribute_group *hotplugable_cpu_attr_groups[] = { -#ifdef CONFIG_KEXEC +#ifdef CONFIG_CRASH_DUMP &crash_note_cpu_attr_group, #endif NULL @@ -265,6 +274,13 @@ static ssize_t print_cpus_offline(struct device *dev, } static DEVICE_ATTR(offline, 0444, print_cpus_offline, NULL); +static ssize_t print_cpus_enabled(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(cpu_enabled_mask)); +} +static DEVICE_ATTR(enabled, 0444, print_cpus_enabled, NULL); + static ssize_t print_cpus_isolated(struct device *dev, struct device_attribute *attr, char *buf) { @@ -284,13 +300,40 @@ static ssize_t print_cpus_isolated(struct device *dev, } static DEVICE_ATTR(isolated, 0444, print_cpus_isolated, NULL); +static ssize_t housekeeping_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const struct cpumask *hk_mask; + + hk_mask = housekeeping_cpumask(HK_TYPE_KERNEL_NOISE); + + if (housekeeping_enabled(HK_TYPE_KERNEL_NOISE)) + return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(hk_mask)); + return sysfs_emit(buf, "\n"); +} +static DEVICE_ATTR_RO(housekeeping); + #ifdef CONFIG_NO_HZ_FULL -static ssize_t print_cpus_nohz_full(struct device *dev, - struct device_attribute *attr, char *buf) +static ssize_t nohz_full_show(struct device *dev, + struct device_attribute *attr, + char *buf) { - return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(tick_nohz_full_mask)); + if (cpumask_available(tick_nohz_full_mask)) + return sysfs_emit(buf, "%*pbl\n", + cpumask_pr_args(tick_nohz_full_mask)); + return sysfs_emit(buf, "\n"); } -static DEVICE_ATTR(nohz_full, 0444, print_cpus_nohz_full, NULL); +static DEVICE_ATTR_RO(nohz_full); +#endif + +#ifdef CONFIG_CRASH_HOTPLUG +static ssize_t crash_hotplug_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%d\n", crash_check_hotplug_support()); +} +static DEVICE_ATTR_RO(crash_hotplug); #endif static void cpu_device_release(struct device *dev) @@ -299,7 +342,7 @@ static void cpu_device_release(struct device *dev) * This is an empty function to prevent the driver core from spitting a * warning at us. Yes, I know this is directly opposite of what the * documentation for the driver core and kobjects say, and the author - * of this code has already been publically ridiculed for doing + * of this code has already been publicly ridiculed for doing * something as foolish as this. However, at this point in time, it is * the only way to handle the issue of statically allocated cpu * devices. The different architectures will have their cpu device @@ -336,7 +379,7 @@ static ssize_t print_cpu_modalias(struct device *dev, return len; } -static int cpu_uevent(struct device *dev, struct kobj_uevent_env *env) +static int cpu_uevent(const struct device *dev, struct kobj_uevent_env *env) { char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL); if (buf) { @@ -348,6 +391,20 @@ static int cpu_uevent(struct device *dev, struct kobj_uevent_env *env) } #endif +const struct bus_type cpu_subsys = { + .name = "cpu", + .dev_name = "cpu", + .match = cpu_subsys_match, +#ifdef CONFIG_HOTPLUG_CPU + .online = cpu_subsys_online, + .offline = cpu_subsys_offline, +#endif +#ifdef CONFIG_GENERIC_CPU_AUTOPROBE + .uevent = cpu_uevent, +#endif +}; +EXPORT_SYMBOL_GPL(cpu_subsys); + /* * register_cpu - Setup a sysfs device for a CPU. * @cpu - cpu->hotpluggable field set to 1 will generate a control file in @@ -368,9 +425,6 @@ int register_cpu(struct cpu *cpu, int num) cpu->dev.offline_disabled = !cpu->hotpluggable; cpu->dev.offline = !cpu_online(num); cpu->dev.of_node = of_get_cpu_node(num, NULL); -#ifdef CONFIG_GENERIC_CPU_AUTOPROBE - cpu->dev.bus->uevent = cpu_uevent; -#endif cpu->dev.groups = common_cpu_attr_groups; if (cpu->hotpluggable) cpu->dev.groups = hotplugable_cpu_attr_groups; @@ -384,6 +438,7 @@ int register_cpu(struct cpu *cpu, int num) register_cpu_under_node(num, cpu_to_node(num)); dev_pm_qos_expose_latency_limit(&cpu->dev, PM_QOS_RESUME_LATENCY_NO_CONSTRAINT); + set_cpu_enabled(num, true); return 0; } @@ -465,10 +520,15 @@ static struct attribute *cpu_root_attrs[] = { &cpu_attrs[2].attr.attr, &dev_attr_kernel_max.attr, &dev_attr_offline.attr, + &dev_attr_enabled.attr, &dev_attr_isolated.attr, + &dev_attr_housekeeping.attr, #ifdef CONFIG_NO_HZ_FULL &dev_attr_nohz_full.attr, #endif +#ifdef CONFIG_CRASH_HOTPLUG + &dev_attr_crash_hotplug.attr, +#endif #ifdef CONFIG_GENERIC_CPU_AUTOPROBE &dev_attr_modalias.attr, #endif @@ -487,94 +547,81 @@ static const struct attribute_group *cpu_root_attr_groups[] = { bool cpu_is_hotpluggable(unsigned int cpu) { struct device *dev = get_cpu_device(cpu); - return dev && container_of(dev, struct cpu, dev)->hotpluggable; + return dev && container_of(dev, struct cpu, dev)->hotpluggable + && tick_nohz_cpu_hotpluggable(cpu); } EXPORT_SYMBOL_GPL(cpu_is_hotpluggable); #ifdef CONFIG_GENERIC_CPU_DEVICES -static DEFINE_PER_CPU(struct cpu, cpu_devices); -#endif - -static void __init cpu_dev_register_generic(void) -{ -#ifdef CONFIG_GENERIC_CPU_DEVICES - int i; - - for_each_possible_cpu(i) { - if (register_cpu(&per_cpu(cpu_devices, i), i)) - panic("Failed to register CPU device"); - } -#endif -} +DEFINE_PER_CPU(struct cpu, cpu_devices); -#ifdef CONFIG_GENERIC_CPU_VULNERABILITIES - -ssize_t __weak cpu_show_meltdown(struct device *dev, - struct device_attribute *attr, char *buf) +bool __weak arch_cpu_is_hotpluggable(int cpu) { - return sysfs_emit(buf, "Not affected\n"); + return false; } -ssize_t __weak cpu_show_spectre_v1(struct device *dev, - struct device_attribute *attr, char *buf) +int __weak arch_register_cpu(int cpu) { - return sysfs_emit(buf, "Not affected\n"); -} + struct cpu *c = &per_cpu(cpu_devices, cpu); -ssize_t __weak cpu_show_spectre_v2(struct device *dev, - struct device_attribute *attr, char *buf) -{ - return sysfs_emit(buf, "Not affected\n"); -} + c->hotpluggable = arch_cpu_is_hotpluggable(cpu); -ssize_t __weak cpu_show_spec_store_bypass(struct device *dev, - struct device_attribute *attr, char *buf) -{ - return sysfs_emit(buf, "Not affected\n"); + return register_cpu(c, cpu); } -ssize_t __weak cpu_show_l1tf(struct device *dev, - struct device_attribute *attr, char *buf) +#ifdef CONFIG_HOTPLUG_CPU +void __weak arch_unregister_cpu(int num) { - return sysfs_emit(buf, "Not affected\n"); + unregister_cpu(&per_cpu(cpu_devices, num)); } +#endif /* CONFIG_HOTPLUG_CPU */ +#endif /* CONFIG_GENERIC_CPU_DEVICES */ -ssize_t __weak cpu_show_mds(struct device *dev, - struct device_attribute *attr, char *buf) +static void __init cpu_dev_register_generic(void) { - return sysfs_emit(buf, "Not affected\n"); -} + int i, ret; -ssize_t __weak cpu_show_tsx_async_abort(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - return sysfs_emit(buf, "Not affected\n"); -} + if (!IS_ENABLED(CONFIG_GENERIC_CPU_DEVICES)) + return; -ssize_t __weak cpu_show_itlb_multihit(struct device *dev, - struct device_attribute *attr, char *buf) -{ - return sysfs_emit(buf, "Not affected\n"); + for_each_present_cpu(i) { + ret = arch_register_cpu(i); + if (ret && ret != -EPROBE_DEFER) + pr_warn("register_cpu %d failed (%d)\n", i, ret); + } } -ssize_t __weak cpu_show_srbds(struct device *dev, +#ifdef CONFIG_GENERIC_CPU_VULNERABILITIES +static ssize_t cpu_show_not_affected(struct device *dev, struct device_attribute *attr, char *buf) { return sysfs_emit(buf, "Not affected\n"); } -ssize_t __weak cpu_show_mmio_stale_data(struct device *dev, - struct device_attribute *attr, char *buf) -{ - return sysfs_emit(buf, "Not affected\n"); -} - -ssize_t __weak cpu_show_retbleed(struct device *dev, - struct device_attribute *attr, char *buf) -{ - return sysfs_emit(buf, "Not affected\n"); -} +#define CPU_SHOW_VULN_FALLBACK(func) \ + ssize_t cpu_show_##func(struct device *, \ + struct device_attribute *, char *) \ + __attribute__((weak, alias("cpu_show_not_affected"))) + +CPU_SHOW_VULN_FALLBACK(meltdown); +CPU_SHOW_VULN_FALLBACK(spectre_v1); +CPU_SHOW_VULN_FALLBACK(spectre_v2); +CPU_SHOW_VULN_FALLBACK(spec_store_bypass); +CPU_SHOW_VULN_FALLBACK(l1tf); +CPU_SHOW_VULN_FALLBACK(mds); +CPU_SHOW_VULN_FALLBACK(tsx_async_abort); +CPU_SHOW_VULN_FALLBACK(itlb_multihit); +CPU_SHOW_VULN_FALLBACK(srbds); +CPU_SHOW_VULN_FALLBACK(mmio_stale_data); +CPU_SHOW_VULN_FALLBACK(retbleed); +CPU_SHOW_VULN_FALLBACK(spec_rstack_overflow); +CPU_SHOW_VULN_FALLBACK(gds); +CPU_SHOW_VULN_FALLBACK(reg_file_data_sampling); +CPU_SHOW_VULN_FALLBACK(ghostwrite); +CPU_SHOW_VULN_FALLBACK(old_microcode); +CPU_SHOW_VULN_FALLBACK(indirect_target_selection); +CPU_SHOW_VULN_FALLBACK(tsa); +CPU_SHOW_VULN_FALLBACK(vmscape); static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL); static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL); @@ -587,6 +634,14 @@ static DEVICE_ATTR(itlb_multihit, 0444, cpu_show_itlb_multihit, NULL); static DEVICE_ATTR(srbds, 0444, cpu_show_srbds, NULL); static DEVICE_ATTR(mmio_stale_data, 0444, cpu_show_mmio_stale_data, NULL); static DEVICE_ATTR(retbleed, 0444, cpu_show_retbleed, NULL); +static DEVICE_ATTR(spec_rstack_overflow, 0444, cpu_show_spec_rstack_overflow, NULL); +static DEVICE_ATTR(gather_data_sampling, 0444, cpu_show_gds, NULL); +static DEVICE_ATTR(reg_file_data_sampling, 0444, cpu_show_reg_file_data_sampling, NULL); +static DEVICE_ATTR(ghostwrite, 0444, cpu_show_ghostwrite, NULL); +static DEVICE_ATTR(old_microcode, 0444, cpu_show_old_microcode, NULL); +static DEVICE_ATTR(indirect_target_selection, 0444, cpu_show_indirect_target_selection, NULL); +static DEVICE_ATTR(tsa, 0444, cpu_show_tsa, NULL); +static DEVICE_ATTR(vmscape, 0444, cpu_show_vmscape, NULL); static struct attribute *cpu_root_vulnerabilities_attrs[] = { &dev_attr_meltdown.attr, @@ -600,6 +655,14 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = { &dev_attr_srbds.attr, &dev_attr_mmio_stale_data.attr, &dev_attr_retbleed.attr, + &dev_attr_spec_rstack_overflow.attr, + &dev_attr_gather_data_sampling.attr, + &dev_attr_reg_file_data_sampling.attr, + &dev_attr_ghostwrite.attr, + &dev_attr_old_microcode.attr, + &dev_attr_indirect_target_selection.attr, + &dev_attr_tsa.attr, + &dev_attr_vmscape.attr, NULL }; @@ -610,9 +673,13 @@ static const struct attribute_group cpu_root_vulnerabilities_group = { 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"); + struct device *dev = bus_get_dev_root(&cpu_subsys); + + if (dev) { + if (sysfs_create_group(&dev->kobj, &cpu_root_vulnerabilities_group)) + pr_err("Unable to register CPU vulnerabilities\n"); + put_device(dev); + } } #else |