[4/4] watchdog: If panicking and we dumped everything, don't re-enable dumping

Message ID 20231220131534.4.Id3a9c7ec2d7d83e4080da6f8662ba2226b40543f@changeid
State New
Headers
Series watchdog: Better handling of concurrent lockups |

Commit Message

Doug Anderson Dec. 20, 2023, 9:15 p.m. UTC
  If, as part of handling a hardlockup or softlockup, we've already
dumped all CPUs and we're just about to panic, don't reenable dumping
and give some other CPU a chance to hop in there and add some
confusing logs right as the panic is happening.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
---

 kernel/watchdog.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
  

Patch

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 11f9577accca..81a8862295d6 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -192,7 +192,8 @@  void watchdog_hardlockup_check(unsigned int cpu, struct pt_regs *regs)
 
 		if (sysctl_hardlockup_all_cpu_backtrace) {
 			trigger_allbutcpu_cpu_backtrace(cpu);
-			clear_bit_unlock(0, &hard_lockup_nmi_warn);
+			if (!hardlockup_panic)
+				clear_bit_unlock(0, &hard_lockup_nmi_warn);
 		}
 
 		if (hardlockup_panic)
@@ -548,7 +549,8 @@  static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
 
 		if (softlockup_all_cpu_backtrace) {
 			trigger_allbutcpu_cpu_backtrace(smp_processor_id());
-			clear_bit_unlock(0, &soft_lockup_nmi_warn);
+			if (!softlockup_panic)
+				clear_bit_unlock(0, &soft_lockup_nmi_warn);
 		}
 
 		add_taint(TAINT_SOFTLOCKUP, LOCKDEP_STILL_OK);