diff options
| author | Steven Rostedt <rostedt@goodmis.org> | 2013-07-16 18:02:28 (GMT) |
|---|---|---|
| committer | Zhang Rui <rui.zhang@intel.com> | 2013-07-22 01:34:46 (GMT) |
| commit | ace120dcf23b3bbba00d797a898481997381052f (patch) | |
| tree | 318a8b24aaf69224392010bb6cd7e56e67a7643a | |
| parent | 94e791f522595e2d5276e6d27a5b3b57f4e1cd8d (diff) | |
| download | linux-ace120dcf23b3bbba00d797a898481997381052f.tar.xz | |
Thermal: Fix lockup of cpu_down()
Commit f1a18a105 "Thermal: CPU Package temperature thermal" had code
that did a get_online_cpus(), run a loop and then do a
put_online_cpus(). The problem is that the loop had an error exit that
would skip the put_online_cpus() part.
In the error exit part of the function, it also did a get_online_cpus(),
run a loop and then put_online_cpus(). The only way to get to the error
exit part is with get_online_cpus() already performed. If this error
condition is hit, the system will be prevented from taking CPUs offline.
The process taking the CPU offline will lock up hard.
Removing the get_online_cpus() removes the lockup as the hotplug CPU
refcount is back to zero.
This was bisected with ktest.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
| -rw-r--r-- | drivers/thermal/x86_pkg_temp_thermal.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/drivers/thermal/x86_pkg_temp_thermal.c b/drivers/thermal/x86_pkg_temp_thermal.c index 810143a..f36950e 100644 --- a/drivers/thermal/x86_pkg_temp_thermal.c +++ b/drivers/thermal/x86_pkg_temp_thermal.c @@ -599,7 +599,6 @@ static int __init pkg_temp_thermal_init(void) return 0; err_ret: - get_online_cpus(); for_each_online_cpu(i) put_core_offline(i); put_online_cpus(); |