x86/cpu: Fix bootup crashes by sanitizing the argument of the 'clearcpuid=' command...

[pandora-kernel.git] / arch / x86 / kernel / microcode_core.c

diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index f2d2a66..29c95d7 100644 (file)
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -256,7 +256,7 @@ static int __init microcode_dev_init(void)
        return 0;
 }
 
-static void microcode_dev_exit(void)
+static void __exit microcode_dev_exit(void)
 {
        misc_deregister(&microcode_dev);
 }
@@ -297,20 +297,31 @@ static ssize_t reload_store(struct sys_device *dev,
                            const char *buf, size_t size)
 {
        unsigned long val;
-       int cpu = dev->id;
-       int ret = 0;
-       char *end;
+       int cpu;
+       ssize_t ret = 0, tmp_ret;
 
-       val = simple_strtoul(buf, &end, 0);
-       if (end == buf)
+       /* allow reload only from the BSP */
+       if (boot_cpu_data.cpu_index != dev->id)
                return -EINVAL;
 
-       if (val == 1) {
-               get_online_cpus();
-               if (cpu_online(cpu))
-                       ret = reload_for_cpu(cpu);
-               put_online_cpus();
+       ret = kstrtoul(buf, 0, &val);
+       if (ret)
+               return ret;
+
+       if (val != 1)
+               return size;
+
+       get_online_cpus();
+       for_each_online_cpu(cpu) {
+               tmp_ret = reload_for_cpu(cpu);
+               if (tmp_ret != 0)
+                       pr_warn("Error reloading microcode on CPU %d\n", cpu);
+
+               /* save retval of the first encountered reload error */
+               if (!ret)
+                       ret = tmp_ret;
        }
+       put_online_cpus();
 
        if (!ret)
                ret = size;
@@ -418,10 +429,8 @@ static int mc_sysdev_add(struct sys_device *sys_dev)
        if (err)
                return err;
 
-       if (microcode_init_cpu(cpu) == UCODE_ERROR) {
-               sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);
+       if (microcode_init_cpu(cpu) == UCODE_ERROR)
                return -EINVAL;
-       }
 
        return err;
 }
@@ -519,10 +528,8 @@ static int __init microcode_init(void)
 
        microcode_pdev = platform_device_register_simple("microcode", -1,
                                                         NULL, 0);
-       if (IS_ERR(microcode_pdev)) {
-               microcode_dev_exit();
+       if (IS_ERR(microcode_pdev))
                return PTR_ERR(microcode_pdev);
-       }
 
        get_online_cpus();
        mutex_lock(&microcode_mutex);
@@ -532,14 +539,12 @@ static int __init microcode_init(void)
        mutex_unlock(&microcode_mutex);
        put_online_cpus();
 
-       if (error) {
-               platform_device_unregister(microcode_pdev);
-               return error;
-       }
+       if (error)
+               goto out_pdev;
 
        error = microcode_dev_init();
        if (error)
-               return error;
+               goto out_sysdev_driver;
 
        register_syscore_ops(&mc_syscore_ops);
        register_hotcpu_notifier(&mc_cpu_notifier);
@@ -548,6 +553,20 @@ static int __init microcode_init(void)
                " <tigran@aivazian.fsnet.co.uk>, Peter Oruba\n");
 
        return 0;
+
+out_sysdev_driver:
+       get_online_cpus();
+       mutex_lock(&microcode_mutex);
+
+       sysdev_driver_unregister(&cpu_sysdev_class, &mc_sysdev_driver);
+
+       mutex_unlock(&microcode_mutex);
+       put_online_cpus();
+
+out_pdev:
+       platform_device_unregister(microcode_pdev);
+       return error;
+
 }
 module_init(microcode_init);