From 4b46ca701bdcdc19fcf32823f9fcabf8236e4e78 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Mon, 25 Aug 2008 17:28:20 -0700 Subject: [PATCH] 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 --- arch/x86/kernel/cpuid.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpuid.c b/arch/x86/kernel/cpuid.c index 14b11b3be31c..23e8316c8357 100644 --- a/arch/x86/kernel/cpuid.c +++ b/arch/x86/kernel/cpuid.c @@ -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; -- 2.20.1