diff options
Diffstat (limited to 'arch/x86/kernel/msr.c')
-rw-r--r-- | arch/x86/kernel/msr.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c index 1f3abe048e93..a153b3905f60 100644 --- a/arch/x86/kernel/msr.c +++ b/arch/x86/kernel/msr.c @@ -117,12 +117,20 @@ static int msr_open(struct inode *inode, struct file *file) { unsigned int cpu = iminor(file->f_path.dentry->d_inode); struct cpuinfo_x86 *c = &cpu_data(cpu); + int ret = 0; - if (cpu >= NR_CPUS || !cpu_online(cpu)) - return -ENXIO; /* No such CPU */ - if (!cpu_has(c, X86_FEATURE_MSR)) - return -EIO; /* MSR not supported */ + lock_kernel(); + cpu = iminor(file->f_path.dentry->d_inode); + if (cpu >= NR_CPUS || !cpu_online(cpu)) { + ret = -ENXIO; /* No such CPU */ + goto out; + } + c = &cpu_data(cpu); + if (!cpu_has(c, X86_FEATURE_MSR)) + ret = -EIO; /* MSR not supported */ +out: + unlock_kernel(); return 0; } |