From ee9fed056f4cd1f68475916428a34d3634be5d30 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 11 Aug 2023 16:48:11 +0800 Subject: [PATCH] timers: Replace BUG_ON()s mainline inclusion from mainline-v6.2-rc1 commit 82ed6f7ef58f9634fe4462dd721902c580f01569 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I7R8WG Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=82ed6f7ef58f9634fe4462dd721902c580f01569 -------------------------------- The timer code still has a few BUG_ON()s left which are crashing the kernel in situations where it still can recover or simply refuse to take an action. Remove the one in the hotplug callback which checks for the CPU being offline. If that happens then the whole hotplug machinery will explode in colourful ways. Replace the rest with WARN_ON_ONCE() and conditional returns where appropriate. Signed-off-by: Thomas Gleixner Tested-by: Guenter Roeck Reviewed-by: Jacob Keller Reviewed-by: Anna-Maria Behnsen Link: https://lore.kernel.org/r/20221123201624.769128888@linutronix.de Signed-off-by: Yu Liao (cherry picked from commit ebf38635249bc25c86a82802a8dee0ad6cd8da01) --- kernel/time/timer.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/kernel/time/timer.c b/kernel/time/timer.c index 6987a4bb44cc..6c8c9805a2fc 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -1140,7 +1140,8 @@ EXPORT_SYMBOL(timer_reduce); */ void add_timer(struct timer_list *timer) { - BUG_ON(timer_pending(timer)); + if (WARN_ON_ONCE(timer_pending(timer))) + return; __mod_timer(timer, timer->expires, MOD_TIMER_NOTPENDING); } EXPORT_SYMBOL(add_timer); @@ -1157,7 +1158,8 @@ void add_timer_on(struct timer_list *timer, int cpu) struct timer_base *new_base, *base; unsigned long flags; - BUG_ON(timer_pending(timer) || !timer->function); + if (WARN_ON_ONCE(timer_pending(timer) || !timer->function)) + return; new_base = get_timer_cpu_base(timer->flags, cpu); @@ -1958,8 +1960,6 @@ int timers_dead_cpu(unsigned int cpu) struct timer_base *new_base; int b, i; - BUG_ON(cpu_online(cpu)); - for (b = 0; b < NR_BASES; b++) { old_base = per_cpu_ptr(&timer_bases[b], cpu); new_base = get_cpu_ptr(&timer_bases[b]); @@ -1976,7 +1976,8 @@ int timers_dead_cpu(unsigned int cpu) */ forward_timer_base(new_base); - BUG_ON(old_base->running_timer); + WARN_ON_ONCE(old_base->running_timer); + old_base->running_timer = NULL; for (i = 0; i < WHEEL_SIZE; i++) migrate_timer_list(new_base, old_base->vectors + i); -- GitLab