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Diffstat (limited to 'arch/x86/kernel/cpuid.c')
-rw-r--r--arch/x86/kernel/cpuid.c16
1 files changed, 11 insertions, 5 deletions
diff --git a/arch/x86/kernel/cpuid.c b/arch/x86/kernel/cpuid.c
index 14b11b3be31c..6a44d6465991 100644
--- a/arch/x86/kernel/cpuid.c
+++ b/arch/x86/kernel/cpuid.c
@@ -36,7 +36,6 @@
36#include <linux/smp_lock.h> 36#include <linux/smp_lock.h>
37#include <linux/major.h> 37#include <linux/major.h>
38#include <linux/fs.h> 38#include <linux/fs.h>
39#include <linux/smp_lock.h>
40#include <linux/device.h> 39#include <linux/device.h>
41#include <linux/cpu.h> 40#include <linux/cpu.h>
42#include <linux/notifier.h> 41#include <linux/notifier.h>
@@ -89,6 +88,8 @@ static ssize_t cpuid_read(struct file *file, char __user *buf,
89 struct cpuid_regs cmd; 88 struct cpuid_regs cmd;
90 int cpu = iminor(file->f_path.dentry->d_inode); 89 int cpu = iminor(file->f_path.dentry->d_inode);
91 u64 pos = *ppos; 90 u64 pos = *ppos;
91 ssize_t bytes = 0;
92 int err = 0;
92 93
93 if (count % 16) 94 if (count % 16)
94 return -EINVAL; /* Invalid chunk size */ 95 return -EINVAL; /* Invalid chunk size */
@@ -96,14 +97,19 @@ static ssize_t cpuid_read(struct file *file, char __user *buf,
96 for (; count; count -= 16) { 97 for (; count; count -= 16) {
97 cmd.eax = pos; 98 cmd.eax = pos;
98 cmd.ecx = pos >> 32; 99 cmd.ecx = pos >> 32;
99 smp_call_function_single(cpu, cpuid_smp_cpuid, &cmd, 1); 100 err = smp_call_function_single(cpu, cpuid_smp_cpuid, &cmd, 1);
100 if (copy_to_user(tmp, &cmd, 16)) 101 if (err)
101 return -EFAULT; 102 break;
103 if (copy_to_user(tmp, &cmd, 16)) {
104 err = -EFAULT;
105 break;
106 }
102 tmp += 16; 107 tmp += 16;
108 bytes += 16;
103 *ppos = ++pos; 109 *ppos = ++pos;
104 } 110 }
105 111
106 return tmp - buf; 112 return bytes ? bytes : err;
107} 113}
108 114
109static int cpuid_open(struct inode *inode, struct file *file) 115static int cpuid_open(struct inode *inode, struct file *file)