Merge branch 'bkl-removal' of git://git.lwn.net/linux-2.6

* 'bkl-removal' of git://git.lwn.net/linux-2.6: (146 commits)
  IB/umad: BKL is not needed for ib_umad_open()
  IB/uverbs: BKL is not needed for ib_uverbs_open()
  bf561-coreb: BKL unneeded for open()
  Call fasync() functions without the BKL
  snd/PCM: fasync BKL pushdown
  ipmi: fasync BKL pushdown
  ecryptfs: fasync BKL pushdown
  Bluetooth VHCI: fasync BKL pushdown
  tty_io: fasync BKL pushdown
  tun: fasync BKL pushdown
  i2o: fasync BKL pushdown
  mpt: fasync BKL pushdown
  Remove BKL from remote_llseek v2
  Make FAT users happier by not deadlocking
  x86-mce: BKL pushdown
  vmwatchdog: BKL pushdown
  vmcp: BKL pushdown
  via-pmu: BKL pushdown
  uml-random: BKL pushdown
  uml-mmapper: BKL pushdown
  ...

1 files changed, 12 insertions, 4 deletions

diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c
index 1f3abe0..a153b39 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;
 }