PREEMPT_RT forces qcom-ipcc's handler to be threaded with interrupts enabled, which triggers a warning in __handle_irq_event_percpu(): irq 173 handler irq_default_primary_handler+0x0/0x10 enabled interrupts WARNING: CPU: 0 PID: 77 at kernel/irq/handle.c:161 __handle_irq_event_percpu+0x4c4/0x4d0 Mark it IRQF_NO_THREAD to avoid running the handler in a threaded context with threadirqs or PREEMPT_RT enabled. Signed-off-by: Eric Chanudet <echanude@xxxxxxxxxx> --- drivers/mailbox/qcom-ipcc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/mailbox/qcom-ipcc.c b/drivers/mailbox/qcom-ipcc.c index 31d58b7d55fe..7e27acf6c0cc 100644 --- a/drivers/mailbox/qcom-ipcc.c +++ b/drivers/mailbox/qcom-ipcc.c @@ -308,7 +308,8 @@ static int qcom_ipcc_probe(struct platform_device *pdev) goto err_mbox; ret = devm_request_irq(&pdev->dev, ipcc->irq, qcom_ipcc_irq_fn, - IRQF_TRIGGER_HIGH | IRQF_NO_SUSPEND, name, ipcc); + IRQF_TRIGGER_HIGH | IRQF_NO_SUSPEND | + IRQF_NO_THREAD, name, ipcc); if (ret < 0) { dev_err(&pdev->dev, "Failed to register the irq: %d\n", ret); goto err_req_irq; -- 2.37.3