From afec3cd1f1f4385ae21f8a9d2dae0d42d38ac8cd Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 28 Jan 2026 10:55:24 +0100 Subject: [PATCH] mailbox: bcm-ferxrm-mailbox: Use default primary handler [ Upstream commit 03843d95a4a4e0ba22ad4fcda65ccf21822b104c ] request_threaded_irq() is invoked with a primary and a secondary handler and no flags are passed. The primary handler is the same as irq_default_primary_handler() so there is no need to have an identical copy. The lack of the IRQF_ONESHOT flag can be dangerous because the interrupt source is not masked while the threaded handler is active. This means, especially on LEVEL typed interrupt lines, the interrupt can fire again before the threaded handler had a chance to run. Use the default primary interrupt handler by specifying NULL and set IRQF_ONESHOT so the interrupt source is masked until the secondary handler is done. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/20260128095540.863589-5-bigeasy@linutronix.de Signed-off-by: Sasha Levin Signed-off-by: Ulrich Hecht --- drivers/mailbox/bcm-flexrm-mailbox.c | 14 ++------------ 1 file changed, 2 insertions(+), 12 deletions(-) diff --git a/drivers/mailbox/bcm-flexrm-mailbox.c b/drivers/mailbox/bcm-flexrm-mailbox.c index 543c4a4a8fca..41aaa09e809f 100644 --- a/drivers/mailbox/bcm-flexrm-mailbox.c +++ b/drivers/mailbox/bcm-flexrm-mailbox.c @@ -1187,14 +1187,6 @@ static int flexrm_debugfs_stats_show(struct seq_file *file, void *offset) /* ====== FlexRM interrupt handler ===== */ -static irqreturn_t flexrm_irq_event(int irq, void *dev_id) -{ - /* We only have MSI for completions so just wakeup IRQ thread */ - /* Ring related errors will be informed via completion descriptors */ - - return IRQ_WAKE_THREAD; -} - static irqreturn_t flexrm_irq_thread(int irq, void *dev_id) { flexrm_process_completions(dev_id); @@ -1285,10 +1277,8 @@ static int flexrm_startup(struct mbox_chan *chan) ret = -ENODEV; goto fail_free_cmpl_memory; } - ret = request_threaded_irq(ring->irq, - flexrm_irq_event, - flexrm_irq_thread, - 0, dev_name(ring->mbox->dev), ring); + ret = request_threaded_irq(ring->irq, NULL, flexrm_irq_thread, + IRQF_ONESHOT, dev_name(ring->mbox->dev), ring); if (ret) { dev_err(ring->mbox->dev, "failed to request ring%d IRQ\n", ring->num);