diff options
| -rw-r--r-- | arch/x86/include/asm/mce.h | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/dev-mcelog.c | 47 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/mce-inject.c | 66 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/mce-internal.h | 6 |
4 files changed, 61 insertions, 62 deletions
diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h index 3f9a3d2a5209..181264989db5 100644 --- a/arch/x86/include/asm/mce.h +++ b/arch/x86/include/asm/mce.h @@ -285,10 +285,6 @@ int mce_notify_irq(void); DECLARE_PER_CPU(struct mce, injectm); -extern void register_mce_write_callback(ssize_t (*)(struct file *filp, - const char __user *ubuf, - size_t usize, loff_t *off)); - /* Disable CMCI/polling for MCA bank claimed by firmware */ extern void mce_disable_bank(int bank); diff --git a/arch/x86/kernel/cpu/mcheck/dev-mcelog.c b/arch/x86/kernel/cpu/mcheck/dev-mcelog.c index 9c632cb88546..a80427c30c93 100644 --- a/arch/x86/kernel/cpu/mcheck/dev-mcelog.c +++ b/arch/x86/kernel/cpu/mcheck/dev-mcelog.c @@ -17,6 +17,8 @@ #include "mce-internal.h" +static BLOCKING_NOTIFIER_HEAD(mce_injector_chain); + static DEFINE_MUTEX(mce_chrdev_read_mutex); static char mce_helper[128]; @@ -345,24 +347,49 @@ static long mce_chrdev_ioctl(struct file *f, unsigned int cmd, } } -static ssize_t (*mce_write)(struct file *filp, const char __user *ubuf, - size_t usize, loff_t *off); +void mce_register_injector_chain(struct notifier_block *nb) +{ + blocking_notifier_chain_register(&mce_injector_chain, nb); +} +EXPORT_SYMBOL_GPL(mce_register_injector_chain); -void register_mce_write_callback(ssize_t (*fn)(struct file *filp, - const char __user *ubuf, - size_t usize, loff_t *off)) +void mce_unregister_injector_chain(struct notifier_block *nb) { - mce_write = fn; + blocking_notifier_chain_unregister(&mce_injector_chain, nb); } -EXPORT_SYMBOL_GPL(register_mce_write_callback); +EXPORT_SYMBOL_GPL(mce_unregister_injector_chain); static ssize_t mce_chrdev_write(struct file *filp, const char __user *ubuf, size_t usize, loff_t *off) { - if (mce_write) - return mce_write(filp, ubuf, usize, off); - else + struct mce m; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + /* + * There are some cases where real MSR reads could slip + * through. + */ + if (!boot_cpu_has(X86_FEATURE_MCE) || !boot_cpu_has(X86_FEATURE_MCA)) + return -EIO; + + if ((unsigned long)usize > sizeof(struct mce)) + usize = sizeof(struct mce); + if (copy_from_user(&m, ubuf, usize)) + return -EFAULT; + + if (m.extcpu >= num_possible_cpus() || !cpu_online(m.extcpu)) return -EINVAL; + + /* + * Need to give user space some time to set everything up, + * so do it a jiffie or two later everywhere. + */ + schedule_timeout(2); + + blocking_notifier_call_chain(&mce_injector_chain, 0, &m); + + return usize; } static const struct file_operations mce_chrdev_ops = { diff --git a/arch/x86/kernel/cpu/mcheck/mce-inject.c b/arch/x86/kernel/cpu/mcheck/mce-inject.c index 7170186938e5..c21c1a73712a 100644 --- a/arch/x86/kernel/cpu/mcheck/mce-inject.c +++ b/arch/x86/kernel/cpu/mcheck/mce-inject.c @@ -283,42 +283,24 @@ static void __maybe_unused raise_mce(struct mce *m) } } -#ifdef CONFIG_X86_MCELOG_LEGACY -/* Error injection interface */ -static ssize_t mce_write(struct file *filp, const char __user *ubuf, - size_t usize, loff_t *off) +static int mce_inject_raise(struct notifier_block *nb, unsigned long val, + void *data) { - struct mce m; - - if (!capable(CAP_SYS_ADMIN)) - return -EPERM; - /* - * There are some cases where real MSR reads could slip - * through. - */ - if (!boot_cpu_has(X86_FEATURE_MCE) || !boot_cpu_has(X86_FEATURE_MCA)) - return -EIO; - - if ((unsigned long)usize > sizeof(struct mce)) - usize = sizeof(struct mce); - if (copy_from_user(&m, ubuf, usize)) - return -EFAULT; - - if (m.extcpu >= num_possible_cpus() || !cpu_online(m.extcpu)) - return -EINVAL; + struct mce *m = (struct mce *)data; - /* - * Need to give user space some time to set everything up, - * so do it a jiffie or two later everywhere. - */ - schedule_timeout(2); + if (!m) + return NOTIFY_DONE; mutex_lock(&mce_inject_mutex); - raise_mce(&m); + raise_mce(m); mutex_unlock(&mce_inject_mutex); - return usize; + + return NOTIFY_DONE; } -#endif /* CONFIG_X86_MCELOG_LEGACY */ + +static struct notifier_block inject_nb = { + .notifier_call = mce_inject_raise, +}; /* * Caller needs to be make sure this cpu doesn't disappear @@ -719,44 +701,34 @@ static int __init inject_init(void) if (!alloc_cpumask_var(&mce_inject_cpumask, GFP_KERNEL)) return -ENOMEM; -#ifdef CONFIG_X86_MCELOG_LEGACY - register_mce_write_callback(mce_write); -#endif - - register_nmi_handler(NMI_LOCAL, mce_raise_notify, 0, "mce_notify"); - err = debugfs_init(); if (err) { free_cpumask_var(mce_inject_cpumask); return err; } + register_nmi_handler(NMI_LOCAL, mce_raise_notify, 0, "mce_notify"); + mce_register_injector_chain(&inject_nb); + pr_info("Machine check injector initialized\n"); return 0; } -module_init(inject_init); - -/* - * Cannot tolerate unloading currently because we cannot - * guarantee all openers of mce_chrdev will get a reference to us. - */ -#ifndef CONFIG_X86_MCELOG_LEGACY static void __exit inject_exit(void) { + mce_unregister_injector_chain(&inject_nb); + unregister_nmi_handler(NMI_LOCAL, "mce_notify"); + debugfs_remove_recursive(dfs_inj); dfs_inj = NULL; memset(&dfs_fls, 0, sizeof(dfs_fls)); - unregister_nmi_handler(NMI_LOCAL, "mce_notify"); - free_cpumask_var(mce_inject_cpumask); } +module_init(inject_init); module_exit(inject_exit); -#endif - MODULE_LICENSE("GPL"); diff --git a/arch/x86/kernel/cpu/mcheck/mce-internal.h b/arch/x86/kernel/cpu/mcheck/mce-internal.h index 654ad0668d72..098530a93bb7 100644 --- a/arch/x86/kernel/cpu/mcheck/mce-internal.h +++ b/arch/x86/kernel/cpu/mcheck/mce-internal.h @@ -100,7 +100,11 @@ static inline bool mce_cmp(struct mce *m1, struct mce *m2) extern struct device_attribute dev_attr_trigger; #ifdef CONFIG_X86_MCELOG_LEGACY -extern void mce_work_trigger(void); +void mce_work_trigger(void); +void mce_register_injector_chain(struct notifier_block *nb); +void mce_unregister_injector_chain(struct notifier_block *nb); #else static inline void mce_work_trigger(void) { } +static inline void mce_register_injector_chain(struct notifier_block *nb) { } +static inline void mce_unregister_injector_chain(struct notifier_block *nb) { } #endif |