printk(KERN_ERR) from check_hung_task() likely means the bug, but unlike BUG_ON/WARN_ON it doesn't show the kernel version, this complicates the bug-reports investigation.
Add the additional pr_err() to print tainted/release/version like dump_stack_print_info() does, the output becomes: INFO: task perl:504 blocked for more than 2 seconds. Not tainted 3.11.0-rc1-10367-g136bb46-dirty #1763 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. ... While at it, turn the old printk's into pr_err(). Signed-off-by: Oleg Nesterov <o...@redhat.com> --- kernel/hung_task.c | 13 +++++++++---- 1 files changed, 9 insertions(+), 4 deletions(-) diff --git a/kernel/hung_task.c b/kernel/hung_task.c index 6df6149..3e97fb1 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -15,6 +15,7 @@ #include <linux/lockdep.h> #include <linux/export.h> #include <linux/sysctl.h> +#include <linux/utsname.h> /* * The number of tasks checked: @@ -99,10 +100,14 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout) * Ok, the task did not get scheduled for more than 2 minutes, * complain: */ - printk(KERN_ERR "INFO: task %s:%d blocked for more than " - "%ld seconds.\n", t->comm, t->pid, timeout); - printk(KERN_ERR "\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\"" - " disables this message.\n"); + pr_err("INFO: task %s:%d blocked for more than %ld seconds.\n", + t->comm, t->pid, timeout); + pr_err(" %s %s %.*s\n", + print_tainted(), init_utsname()->release, + (int)strcspn(init_utsname()->version, " "), + init_utsname()->version); + pr_err("\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\"" + " disables this message.\n"); sched_show_task(t); debug_show_held_locks(t); -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/