Subject: + hung_task-check-the-value-of-sysctl_hung_task_timeout_sec.patch added to -mm tree To: sdu.liu@xxxxxxxxxx,satoru.takeuchi@xxxxxxxxx,stable@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Fri, 28 Mar 2014 13:24:39 -0700 The patch titled Subject: hung_task: check the value of "sysctl_hung_task_timeout_sec" has been added to the -mm tree. Its filename is hung_task-check-the-value-of-sysctl_hung_task_timeout_sec.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/hung_task-check-the-value-of-sysctl_hung_task_timeout_sec.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/hung_task-check-the-value-of-sysctl_hung_task_timeout_sec.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Liu Hua <sdu.liu@xxxxxxxxxx> Subject: hung_task: check the value of "sysctl_hung_task_timeout_sec" As sysctl_hung_task_timeout_sec is unsigned long, when this value is larger then LONG_MAX/HZ, the function schedule_timeout_interruptible in watchdog will return immediately without sleep and with print : [ 205.452934] schedule_timeout: wrong timeout value ffffffffffffff83 and then the funtion watchdog will call schedule_timeout_interruptible again and again. The screen will be filled with "schedule_timeout: wrong timeout value ffffffffffffff83" This patch does some check and correction in sysctl, to let the function schedule_timeout_interruptible allways get the valid parameter. Signed-off-by: Liu Hua <sdu.liu@xxxxxxxxxx> Tested-by: Satoru Takeuchi <satoru.takeuchi@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> [3.4+] Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/sysctl/kernel.txt | 1 + kernel/sysctl.c | 6 ++++++ 2 files changed, 7 insertions(+) diff -puN Documentation/sysctl/kernel.txt~hung_task-check-the-value-of-sysctl_hung_task_timeout_sec Documentation/sysctl/kernel.txt --- a/Documentation/sysctl/kernel.txt~hung_task-check-the-value-of-sysctl_hung_task_timeout_sec +++ a/Documentation/sysctl/kernel.txt @@ -317,6 +317,7 @@ for more than this value report a warnin This file shows up if CONFIG_DETECT_HUNG_TASK is enabled. 0: means infinite timeout - no checking done. +Possible values to set are in range {0..LONG_MAX/HZ}. ============================================================== diff -puN kernel/sysctl.c~hung_task-check-the-value-of-sysctl_hung_task_timeout_sec kernel/sysctl.c --- a/kernel/sysctl.c~hung_task-check-the-value-of-sysctl_hung_task_timeout_sec +++ a/kernel/sysctl.c @@ -144,6 +144,11 @@ static int min_percpu_pagelist_fract = 8 static int ngroups_max = NGROUPS_MAX; static const int cap_last_cap = CAP_LAST_CAP; +/*this is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs */ +#ifdef CONFIG_DETECT_HUNG_TASK +static unsigned long hung_task_timeout_max = (LONG_MAX/HZ); +#endif + #ifdef CONFIG_INOTIFY_USER #include <linux/inotify.h> #endif @@ -995,6 +1000,7 @@ static struct ctl_table kern_table[] = { .maxlen = sizeof(unsigned long), .mode = 0644, .proc_handler = proc_dohung_task_timeout_secs, + .extra2 = &hung_task_timeout_max, }, { .procname = "hung_task_warnings", _ Patches currently in -mm which might be from sdu.liu@xxxxxxxxxx are hung_task-check-the-value-of-sysctl_hung_task_timeout_sec.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html