diff options
| author | Li Zefan <lizefan@huawei.com> | 2013-09-23 16:43:58 +0800 | 
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2013-09-23 11:10:49 +0200 | 
| commit | cd64647f043e3fd3569bcf068f47f030198ff93a (patch) | |
| tree | c4ff621340758e4dde72ddb8c3a63d32604c0fbb | |
| parent | d8524ae9d6f492a9c6db9f4d89c5f9b8782fa2d5 (diff) | |
hung_task: Change sysctl_hung_task_check_count to 'int'
As 'sysctl_hung_task_check_count' is 'unsigned long' when this
value is assigned to max_count in check_hung_uninterruptible_tasks(),
it's truncated to 'int' type.
This causes a minor artifact: if we write 2^32 to sysctl.hung_task_check_count,
hung task detection will be effectively disabled.
With this fix, it will still truncate the user input to 32 bits, but
reading sysctl.hung_task_check_count reflects the actual truncated value.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/523FFF4E.9050401@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | include/linux/sched/sysctl.h | 2 | ||||
| -rw-r--r-- | kernel/hung_task.c | 2 | ||||
| -rw-r--r-- | kernel/sysctl.c | 5 | 
3 files changed, 5 insertions, 4 deletions
diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h index bf8086b2506e..9552afa733d8 100644 --- a/include/linux/sched/sysctl.h +++ b/include/linux/sched/sysctl.h @@ -2,8 +2,8 @@  #define _SCHED_SYSCTL_H  #ifdef CONFIG_DETECT_HUNG_TASK +extern int	     sysctl_hung_task_check_count;  extern unsigned int  sysctl_hung_task_panic; -extern unsigned long sysctl_hung_task_check_count;  extern unsigned long sysctl_hung_task_timeout_secs;  extern unsigned long sysctl_hung_task_warnings;  extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, diff --git a/kernel/hung_task.c b/kernel/hung_task.c index 3e97fb126e6b..042252383fd2 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -20,7 +20,7 @@  /*   * The number of tasks checked:   */ -unsigned long __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT; +int __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT;  /*   * Limit number of tasks checked in a batch. diff --git a/kernel/sysctl.c b/kernel/sysctl.c index b2f06f3c6a3f..b24ed7f87a14 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -962,9 +962,10 @@ static struct ctl_table kern_table[] = {  	{  		.procname	= "hung_task_check_count",  		.data		= &sysctl_hung_task_check_count, -		.maxlen		= sizeof(unsigned long), +		.maxlen		= sizeof(int),  		.mode		= 0644, -		.proc_handler	= proc_doulongvec_minmax, +		.proc_handler	= proc_dointvec_minmax, +		.extra1		= &zero,  	},  	{  		.procname	= "hung_task_timeout_secs",  | 
