Red Hat Bugzilla – Bug 145619
msr device nodes created in wrong place
Last modified: 2007-11-30 17:07:15 EST
Description of problem:
Loading the msr kernel module creates /dev/msr0, but x86info looks for
/dev/cpu/0/msr, and gives an error when the device isn't found.
Creating a symlink /dev/cpu/0/msr -> /dev/msr0 fixes the problem.
Steps to Reproduce:
1. modprobe msr
2. x86info -a
x86info output contains line
/dev/cpu/0/msr: No such file or directory
Confirmed on two different single CPU systems (Celeron-Mendocino and
these *should* be in /dev/cpu/0/msr, so udev is creating them in the wrong place.
# ls -l /dev/cpu*
crw------- 1 root root 203, 0 Mar 31 10:18 /dev/cpu0
crw------- 1 root root 203, 1 Mar 31 10:18 /dev/cpu1
Same problem with cpuid files. See
/dev/cpu/0/cpuid: No such file or directory
error from x86info
problem still exists in released RHEL4
On x86_64 Fedora 3, the "msr" device nodes are absent altogether (and there is
no msr.ko loadable module). After I do "mknod msr0 c 202 0", "mknod msr1 c 202
1" (and so forth), access to the msr's seems to work fine. K.O.
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.