From 881a841f4ae268207c29721532406ad061e41857 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Thu, 18 Oct 2007 03:05:14 -0700 Subject: [PATCH] cpu hotplug: msr: fix cpu hotplug error handling Do msr_device_create() in CPU_UP_PREPARE instead of CPU_ONLINE. Cc: "H. Peter Anvin" Signed-off-by: Akinobu Mita Cc: Gautham R Shenoy Cc: Oleg Nesterov Cc: Andi Kleen Cc: Jan Beulich Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/kernel/msr.c | 35 ++++++++++++++++++++--------------- 1 file changed, 20 insertions(+), 15 deletions(-) diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c index df85c9c1360..e0d5e82e64b 100644 --- a/arch/x86/kernel/msr.c +++ b/arch/x86/kernel/msr.c @@ -133,37 +133,42 @@ static const struct file_operations msr_fops = { .open = msr_open, }; -static int __cpuinit msr_device_create(int i) +static int msr_device_create(int cpu) { - int err = 0; struct device *dev; - dev = device_create(msr_class, NULL, MKDEV(MSR_MAJOR, i), "msr%d",i); - if (IS_ERR(dev)) - err = PTR_ERR(dev); - return err; + dev = device_create(msr_class, NULL, MKDEV(MSR_MAJOR, cpu), + "msr%d", cpu); + return IS_ERR(dev) ? PTR_ERR(dev) : 0; +} + +static void msr_device_destroy(int cpu) +{ + device_destroy(msr_class, MKDEV(MSR_MAJOR, cpu)); } static int __cpuinit msr_class_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; + int err = 0; switch (action) { - case CPU_ONLINE: - case CPU_ONLINE_FROZEN: - msr_device_create(cpu); + case CPU_UP_PREPARE: + case CPU_UP_PREPARE_FROZEN: + err = msr_device_create(cpu); break; + case CPU_UP_CANCELED: + case CPU_UP_CANCELED_FROZEN: case CPU_DEAD: case CPU_DEAD_FROZEN: - device_destroy(msr_class, MKDEV(MSR_MAJOR, cpu)); + msr_device_destroy(cpu); break; } - return NOTIFY_OK; + return err ? NOTIFY_BAD : NOTIFY_OK; } -static struct notifier_block __cpuinitdata msr_class_cpu_notifier = -{ +static struct notifier_block __cpuinitdata msr_class_cpu_notifier = { .notifier_call = msr_class_cpu_callback, }; @@ -196,7 +201,7 @@ static int __init msr_init(void) out_class: i = 0; for_each_online_cpu(i) - device_destroy(msr_class, MKDEV(MSR_MAJOR, i)); + msr_device_destroy(i); class_destroy(msr_class); out_chrdev: unregister_chrdev(MSR_MAJOR, "cpu/msr"); @@ -208,7 +213,7 @@ static void __exit msr_exit(void) { int cpu = 0; for_each_online_cpu(cpu) - device_destroy(msr_class, MKDEV(MSR_MAJOR, cpu)); + msr_device_destroy(cpu); class_destroy(msr_class); unregister_chrdev(MSR_MAJOR, "cpu/msr"); unregister_hotcpu_notifier(&msr_class_cpu_notifier); -- 2.20.1