From 0b962d473af32ec334df271b54ff4973cb2b4c73 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Tue, 15 Dec 2009 15:13:07 -0800 Subject: [PATCH] x86, msr/cpuid: Register enough minors for the MSR and CPUID drivers register_chrdev() hardcodes registering 256 minors, presumably to avoid breaking old drivers. However, we need to register enough minors so that we have all possible CPUs. checkpatch warns on this patch, but the patch is correct: NR_CPUS here is a static *upper bound* on the *maximum CPU index* (not *number of CPUs!*) and that is what we want. Reported-and-tested-by: Russ Anderson Cc: Tejun Heo Cc: Alan Cox Cc: Takashi Iwai Cc: Alexander Viro Signed-off-by: H. Peter Anvin LKML-Reference: --- arch/x86/kernel/cpuid.c | 5 +++-- arch/x86/kernel/msr.c | 4 ++-- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/cpuid.c b/arch/x86/kernel/cpuid.c index 7ef24a7..cb27fd6 100644 --- a/arch/x86/kernel/cpuid.c +++ b/arch/x86/kernel/cpuid.c @@ -187,7 +187,8 @@ static int __init cpuid_init(void) int i, err = 0; i = 0; - if (register_chrdev(CPUID_MAJOR, "cpu/cpuid", &cpuid_fops)) { + if (__register_chrdev(CPUID_MAJOR, 0, NR_CPUS, + "cpu/cpuid", &cpuid_fops)) { printk(KERN_ERR "cpuid: unable to get major %d for cpuid\n", CPUID_MAJOR); err = -EBUSY; @@ -216,7 +217,7 @@ out_class: } class_destroy(cpuid_class); out_chrdev: - unregister_chrdev(CPUID_MAJOR, "cpu/cpuid"); + __unregister_chrdev(CPUID_MAJOR, 0, NR_CPUS, "cpu/cpuid"); out: return err; } diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c index 572b07e..4bd93c9 100644 --- a/arch/x86/kernel/msr.c +++ b/arch/x86/kernel/msr.c @@ -246,7 +246,7 @@ static int __init msr_init(void) int i, err = 0; i = 0; - if (register_chrdev(MSR_MAJOR, "cpu/msr", &msr_fops)) { + if (__register_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr", &msr_fops)) { printk(KERN_ERR "msr: unable to get major %d for msr\n", MSR_MAJOR); err = -EBUSY; @@ -274,7 +274,7 @@ out_class: msr_device_destroy(i); class_destroy(msr_class); out_chrdev: - unregister_chrdev(MSR_MAJOR, "cpu/msr"); + __unregister_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr"); out: return err; } -- 2.7.4