From fb151864763084c4d5187f4d42af6476f57dbb4a Mon Sep 17 00:00:00 2001 From: Yongliang Gao Date: Thu, 13 Jun 2024 11:31:59 +0800 Subject: [PATCH] hung_task: ignore hung_task_warnings when hung_task_panic is enabled If hung_task_panic is enabled, don't consider the value of hung_task_warnings and display the information of the hung tasks. In some cases, hung_task_panic might not be initially set up, after several hung tasks occur, the hung_task_warnings count reaches zero. If hung_task_panic is set up later, it may not display any helpful hung task info in dmesg, only showing messages like: Kernel panic - not syncing: hung_task: blocked tasks CPU: 3 PID: 58 Comm: khungtaskd Not tainted 6.10.0-rc3 #19 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Call Trace: panic+0x2f3/0x320 watchdog+0x2dd/0x510 ? __pfx_watchdog+0x10/0x10 kthread+0xe0/0x110 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2f/0x40 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 Link: https://lkml.kernel.org/r/20240613033159.3446265-1-leonylgao@gmail.com Signed-off-by: Yongliang Gao Reviewed-by: Huang Cun Cc: Joel Granados Cc: John Siddle Cc: Kent Overstreet Signed-off-by: Andrew Morton --- kernel/hung_task.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/hung_task.c b/kernel/hung_task.c index 1d92016b0b3c42..6ca859715d8a37 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -127,7 +127,7 @@ 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: */ - if (sysctl_hung_task_warnings) { + if (sysctl_hung_task_warnings || hung_task_call_panic) { if (sysctl_hung_task_warnings > 0) sysctl_hung_task_warnings--; pr_err("INFO: task %s:%d blocked for more than %ld seconds.\n",