tick_check_percpu() calls cpumask_equal() even if curdev->cpumask == cpumask_of(cpu). Fix it. Caught with CONFIG_DEBUG_BITMAP: [ 0.077622] Call trace: [ 0.077637] __bitmap_check_params+0x144/0x250 [ 0.077675] tick_check_replacement+0xac/0x320 [ 0.077716] tick_check_new_device+0x50/0x110 [ 0.077747] clockevents_register_device+0x74/0x1c0 [ 0.077779] dummy_timer_starting_cpu+0x6c/0x80 [ 0.077817] cpuhp_invoke_callback+0x104/0x20c [ 0.077856] cpuhp_invoke_callback_range+0x70/0xf0 [ 0.077890] notify_cpu_starting+0xac/0xcc [ 0.077921] secondary_start_kernel+0xe4/0x154 [ 0.077951] __secondary_switched+0xa0/0xa4 [ 0.077992] ---[ end trace 0000000000000000 ]--- [ 0.078021] b1: ffffbfec4703b890 [ 0.078031] b2: ffffbfec4703b890 [ 0.078043] b3: 0 [ 0.078052] nbits: 256 [ 0.078065] start: 0 [ 0.078075] off: 0 [ 0.078086] Bitmap: parameters check failed [ 0.078095] include/linux/bitmap.h [419]: bitmap_equal Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx> --- kernel/time/tick-common.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index fdd5ae1a074b..7205f76f8d10 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -290,13 +290,15 @@ static bool tick_check_percpu(struct clock_event_device *curdev, { if (!cpumask_test_cpu(cpu, newdev->cpumask)) return false; - if (cpumask_equal(newdev->cpumask, cpumask_of(cpu))) + if (newdev->cpumask == cpumask_of(cpu) || + cpumask_equal(newdev->cpumask, cpumask_of(cpu))) return true; /* Check if irq affinity can be set */ if (newdev->irq >= 0 && !irq_can_set_affinity(newdev->irq)) return false; /* Prefer an existing cpu local device */ - if (curdev && cpumask_equal(curdev->cpumask, cpumask_of(cpu))) + if (curdev && (curdev->cpumask == cpumask_of(cpu) || + cpumask_equal(curdev->cpumask, cpumask_of(cpu)))) return false; return true; } -- 2.34.1