Merge branch 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next

Pull x86 RAS changes from Ingo Molnar:
 "Improve mcheck device initialization and bootstrap robustness"

* 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  mce: Panic when a core has reached a timeout
  x86/mce: Improve mcheck_init_device() error handling

1 files changed, 41 insertions, 9 deletions

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 68317c80de7f..6cc800381d14 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -704,8 +704,7 @@ static int mce_timed_out(u64 *t)
         if (!mca_cfg.monarch_timeout)
                 goto out;
         if ((s64)*t < SPINUNIT) {
-                /* CHECKME: Make panic default for 1 too? */
-                if (mca_cfg.tolerant < 1)
+                if (mca_cfg.tolerant <= 1)
                         mce_panic("Timeout synchronizing machine check over CPUs",
                                   NULL, NULL);
                 cpu_missing = 1;
@@ -2437,32 +2436,65 @@ static __init int mcheck_init_device(void)
         int err;
         int i = 0;
 
-        if (!mce_available(&boot_cpu_data))
-                return -EIO;
+        if (!mce_available(&boot_cpu_data)) {
+                err = -EIO;
+                goto err_out;
+        }
 
-        zalloc_cpumask_var(&mce_device_initialized, GFP_KERNEL);
+        if (!zalloc_cpumask_var(&mce_device_initialized, GFP_KERNEL)) {
+                err = -ENOMEM;
+                goto err_out;
+        }
 
         mce_init_banks();
 
         err = subsys_system_register(&mce_subsys, NULL);
         if (err)
-                return err;
+                goto err_out_mem;
 
         cpu_notifier_register_begin();
         for_each_online_cpu(i) {
                 err = mce_device_create(i);
                 if (err) {
                         cpu_notifier_register_done();
-                        return err;
+                        goto err_device_create;
                 }
         }
 
-        register_syscore_ops(&mce_syscore_ops);
         __register_hotcpu_notifier(&mce_cpu_notifier);
         cpu_notifier_register_done();
 
+        register_syscore_ops(&mce_syscore_ops);
+
         /* register character device /dev/mcelog */
-        misc_register(&mce_chrdev_device);
+        err = misc_register(&mce_chrdev_device);
+        if (err)
+                goto err_register;
+
+        return 0;
+
+err_register:
+        unregister_syscore_ops(&mce_syscore_ops);
+
+        cpu_notifier_register_begin();
+        __unregister_hotcpu_notifier(&mce_cpu_notifier);
+        cpu_notifier_register_done();
+
+err_device_create:
+        /*
+         * We didn't keep track of which devices were created above, but
+         * even if we had, the set of online cpus might have changed.
+         * Play safe and remove for every possible cpu, since
+         * mce_device_remove() will do the right thing.
+         */
+        for_each_possible_cpu(i)
+                mce_device_remove(i);
+
+err_out_mem:
+        free_cpumask_var(mce_device_initialized);
+
+err_out:
+        pr_err("Unable to init device /dev/mcelog (rc: %d)\n", err);
 
         return err;
 }