Any lockup or stall detector notifies about unexpected lack of progress. It's better to know about these splats at investigating further problems. This patch set TAINT_LOCKUP at: - softlockup (CONFIG_SOFTLOCKUP_DETECTOR) - hardlockup (CONFIG_HARDLOCKUP_DETECTOR) - RCU stall (Documentation/RCU/stallwarn.txt) - hung task (CONFIG_DETECT_HUNG_TASK) - stuck in workqueues (CONFIG_WQ_WATCHDOG) Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx> Acked-by: Paul E. McKenney <paulmck@xxxxxxxxxx> (RCU part) Link: https://lore.kernel.org/lkml/157503370645.8187.6335564487789994134.stgit@buzz/ (v1) --- Documentation/admin-guide/tainted-kernels.rst | 4 ++++ kernel/hung_task.c | 2 ++ kernel/rcu/tree_stall.h | 1 + kernel/watchdog_hld.c | 1 + kernel/workqueue.c | 1 + 5 files changed, 9 insertions(+) diff --git a/Documentation/admin-guide/tainted-kernels.rst b/Documentation/admin-guide/tainted-kernels.rst index 55d45211cb41..13249240283c 100644 --- a/Documentation/admin-guide/tainted-kernels.rst +++ b/Documentation/admin-guide/tainted-kernels.rst @@ -153,6 +153,10 @@ More detailed explanation for tainting module signature. 14) ``L`` if a lockup has previously occurred on the system. + - soft/hardlockup, see Documentation/admin-guide/lockup-watchdogs.rst + - RCU stall, see Documentation/RCU/stallwarn.txt + - hung task detected, see CONFIG_DETECT_HUNG_TASK + - kernel workqueue lockup, see CONFIG_WQ_WATCHDOG 15) ``K`` if the kernel has been live patched. diff --git a/kernel/hung_task.c b/kernel/hung_task.c index 14a625c16cb3..521eb2fbf5fc 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -139,6 +139,8 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout) hung_task_show_lock = true; } + add_taint(TAINT_LOCKUP, LOCKDEP_STILL_OK); + touch_nmi_watchdog(); } diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h index c0b8c458d8a6..181495efff80 100644 --- a/kernel/rcu/tree_stall.h +++ b/kernel/rcu/tree_stall.h @@ -74,6 +74,7 @@ early_initcall(check_cpu_stall_init); /* If so specified via sysctl, panic, yielding cleaner stall-warning output. */ static void panic_on_rcu_stall(void) { + add_taint(TAINT_LOCKUP, LOCKDEP_STILL_OK); if (sysctl_panic_on_rcu_stall) panic("RCU Stall\n"); } diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c index 247bf0b1582c..f77256f47422 100644 --- a/kernel/watchdog_hld.c +++ b/kernel/watchdog_hld.c @@ -152,6 +152,7 @@ static void watchdog_overflow_callback(struct perf_event *event, !test_and_set_bit(0, &hardlockup_allcpu_dumped)) trigger_allbutself_cpu_backtrace(); + add_taint(TAINT_LOCKUP, LOCKDEP_STILL_OK); if (hardlockup_panic) nmi_panic(regs, "Hard LOCKUP"); diff --git a/kernel/workqueue.c b/kernel/workqueue.c index cfc923558e04..1b3c81d87a0d 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -5774,6 +5774,7 @@ static void wq_watchdog_timer_fn(struct timer_list *unused) pr_cont_pool_info(pool); pr_cont(" stuck for %us!\n", jiffies_to_msecs(jiffies - pool_ts) / 1000); + add_taint(TAINT_LOCKUP, LOCKDEP_STILL_OK); } }
