x86: cpuid: propagate error from smp_call_function_single()

Propagate error (-ENXIO) from smp_call_function_single() in the CPUID
driver.  This can happen when a CPU is unplugged while the CPUID
driver is open.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
H. Peter Anvin 2008-08-25 17:28:20 -07:00
parent c6f31932d0
commit 4b46ca701b
1 changed files with 4 additions and 1 deletions

View File

@ -89,6 +89,7 @@ static ssize_t cpuid_read(struct file *file, char __user *buf,
struct cpuid_regs cmd;
int cpu = iminor(file->f_path.dentry->d_inode);
u64 pos = *ppos;
int err;
if (count % 16)
return -EINVAL; /* Invalid chunk size */
@ -96,7 +97,9 @@ static ssize_t cpuid_read(struct file *file, char __user *buf,
for (; count; count -= 16) {
cmd.eax = pos;
cmd.ecx = pos >> 32;
smp_call_function_single(cpu, cpuid_smp_cpuid, &cmd, 1);
err = smp_call_function_single(cpu, cpuid_smp_cpuid, &cmd, 1);
if (err)
return err;
if (copy_to_user(tmp, &cmd, 16))
return -EFAULT;
tmp += 16;