| From 31a63ee7cc1abdb3923e4a5ef5112b677f09fd65 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Wed, 20 Oct 2021 17:25:22 +0100 |
| Subject: irq: mips: avoid nested irq_enter() |
| |
| From: Mark Rutland <mark.rutland@arm.com> |
| |
| [ Upstream commit c65b52d02f6c1a06ddb20cba175ad49eccd6410d ] |
| |
| As bcm6345_l1_irq_handle() is a chained irqchip handler, it will be |
| invoked within the context of the root irqchip handler, which must have |
| entered IRQ context already. |
| |
| When bcm6345_l1_irq_handle() calls arch/mips's do_IRQ() , this will nest |
| another call to irq_enter(), and the resulting nested increment to |
| `rcu_data.dynticks_nmi_nesting` will cause rcu_is_cpu_rrupt_from_idle() |
| to fail to identify wakeups from idle, resulting in failure to preempt, |
| and RCU stalls. |
| |
| Chained irqchip handlers must invoke IRQ handlers by way of thee core |
| irqchip code, i.e. generic_handle_irq() or generic_handle_domain_irq() |
| and should not call do_IRQ(), which is intended only for root irqchip |
| handlers. |
| |
| Fix bcm6345_l1_irq_handle() by calling generic_handle_irq() directly. |
| |
| Fixes: c7c42ec2baa1de7a ("irqchips/bmips: Add bcm6345-l1 interrupt controller") |
| Signed-off-by: Mark Rutland <mark.rutland@arm.com> |
| Reviewed-by: Marc Zyngier <maz@kernel.org> |
| Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> |
| Cc: Thomas Gleixner <tglx@linutronix.de> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/irqchip/irq-bcm6345-l1.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| diff --git a/drivers/irqchip/irq-bcm6345-l1.c b/drivers/irqchip/irq-bcm6345-l1.c |
| index e3483789f4df3..1bd0621c4ce2a 100644 |
| --- a/drivers/irqchip/irq-bcm6345-l1.c |
| +++ b/drivers/irqchip/irq-bcm6345-l1.c |
| @@ -140,7 +140,7 @@ static void bcm6345_l1_irq_handle(struct irq_desc *desc) |
| for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) { |
| irq = irq_linear_revmap(intc->domain, base + hwirq); |
| if (irq) |
| - do_IRQ(irq); |
| + generic_handle_irq(irq); |
| else |
| spurious_interrupt(); |
| } |
| -- |
| 2.33.0 |
| |