diff options
Diffstat (limited to 'arch/x86/kernel/cpu/microcode/core.c')
-rw-r--r-- | arch/x86/kernel/cpu/microcode/core.c | 115 |
1 files changed, 11 insertions, 104 deletions
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index 239ff5fcec6a..ad57e0e4d674 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -373,101 +373,10 @@ static int apply_microcode_on_target(int cpu) return ret; } -#ifdef CONFIG_MICROCODE_OLD_INTERFACE -static int do_microcode_update(const void __user *buf, size_t size) -{ - int error = 0; - int cpu; - - for_each_online_cpu(cpu) { - struct ucode_cpu_info *uci = ucode_cpu_info + cpu; - enum ucode_state ustate; - - if (!uci->valid) - continue; - - ustate = microcode_ops->request_microcode_user(cpu, buf, size); - if (ustate == UCODE_ERROR) { - error = -1; - break; - } else if (ustate == UCODE_NEW) { - apply_microcode_on_target(cpu); - } - } - - return error; -} - -static int microcode_open(struct inode *inode, struct file *file) -{ - return capable(CAP_SYS_RAWIO) ? stream_open(inode, file) : -EPERM; -} - -static ssize_t microcode_write(struct file *file, const char __user *buf, - size_t len, loff_t *ppos) -{ - ssize_t ret = -EINVAL; - unsigned long nr_pages = totalram_pages(); - - if ((len >> PAGE_SHIFT) > nr_pages) { - pr_err("too much data (max %ld pages)\n", nr_pages); - return ret; - } - - cpus_read_lock(); - mutex_lock(µcode_mutex); - - if (do_microcode_update(buf, len) == 0) - ret = (ssize_t)len; - - if (ret > 0) - perf_check_microcode(); - - mutex_unlock(µcode_mutex); - cpus_read_unlock(); - - return ret; -} - -static const struct file_operations microcode_fops = { - .owner = THIS_MODULE, - .write = microcode_write, - .open = microcode_open, - .llseek = no_llseek, -}; - -static struct miscdevice microcode_dev = { - .minor = MICROCODE_MINOR, - .name = "microcode", - .nodename = "cpu/microcode", - .fops = µcode_fops, -}; - -static int __init microcode_dev_init(void) -{ - int error; - - error = misc_register(µcode_dev); - if (error) { - pr_err("can't misc_register on minor=%d\n", MICROCODE_MINOR); - return error; - } - - return 0; -} - -static void __exit microcode_dev_exit(void) -{ - misc_deregister(µcode_dev); -} -#else -#define microcode_dev_init() 0 -#define microcode_dev_exit() do { } while (0) -#endif - /* fake device for request_firmware */ static struct platform_device *microcode_pdev; +#ifdef CONFIG_MICROCODE_LATE_LOADING /* * Late loading dance. Why the heavy-handed stomp_machine effort? * @@ -584,6 +493,9 @@ static int microcode_reload_late(void) { int ret; + pr_err("Attempting late microcode loading - it is dangerous and taints the kernel.\n"); + pr_err("You should switch to early loading, if possible.\n"); + atomic_set(&late_cpus_in, 0); atomic_set(&late_cpus_out, 0); @@ -632,9 +544,14 @@ put: if (ret == 0) ret = size; + add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK); + return ret; } +static DEVICE_ATTR_WO(reload); +#endif + static ssize_t version_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -651,7 +568,6 @@ static ssize_t pf_show(struct device *dev, return sprintf(buf, "0x%x\n", uci->cpu_sig.pf); } -static DEVICE_ATTR_WO(reload); static DEVICE_ATTR(version, 0444, version_show, NULL); static DEVICE_ATTR(processor_flags, 0444, pf_show, NULL); @@ -804,7 +720,9 @@ static int mc_cpu_down_prep(unsigned int cpu) } static struct attribute *cpu_root_microcode_attrs[] = { +#ifdef CONFIG_MICROCODE_LATE_LOADING &dev_attr_reload.attr, +#endif NULL }; @@ -838,10 +756,7 @@ static int __init microcode_init(void) cpus_read_lock(); mutex_lock(µcode_mutex); - error = subsys_interface_register(&mc_cpu_interface); - if (!error) - perf_check_microcode(); mutex_unlock(µcode_mutex); cpus_read_unlock(); @@ -856,10 +771,6 @@ static int __init microcode_init(void) goto out_driver; } - error = microcode_dev_init(); - if (error) - goto out_ucode_group; - register_syscore_ops(&mc_syscore_ops); cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:starting", mc_cpu_starting, NULL); @@ -870,10 +781,6 @@ static int __init microcode_init(void) return 0; - out_ucode_group: - sysfs_remove_group(&cpu_subsys.dev_root->kobj, - &cpu_root_microcode_group); - out_driver: cpus_read_lock(); mutex_lock(µcode_mutex); |