summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorSteven Rostedt <rostedt@goodmis.org>2013-07-16 20:02:28 +0200
committerZhang Rui <rui.zhang@intel.com>2013-07-22 03:34:46 +0200
commitace120dcf23b3bbba00d797a898481997381052f (patch)
tree318a8b24aaf69224392010bb6cd7e56e67a7643a
parentThermal: x86_pkg_temp: Limit number of pkg temp zones (diff)
downloadlinux-ace120dcf23b3bbba00d797a898481997381052f.tar.xz
linux-ace120dcf23b3bbba00d797a898481997381052f.zip
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.c1
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 810143a6aa33..f36950e4134f 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();