diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2016-09-02 14:45:19 +0200 | 
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2016-09-02 18:06:49 +0200 | 
| commit | fc590c22f9f056ab50190b797f6cacead29f9b75 (patch) | |
| tree | 87719f60da441d05d0ea7f16fb3ba4d926491f5f /kernel | |
| parent | eb0dc47ab6810c432e8193beccd9905ba0db8b22 (diff) | |
genirq: Robustify handle_percpu_devid_irq()
The percpu_devid handler is not robust against spurious interrupts. If a
spurious interrupt happens and no action is installed then the handler
crashes with a NULL pointer dereference.
Add a sanity check for this and log the wreckage once in dmesg.
Reported-by: Majun <majun258@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: guohanjun@huawei.com
Cc: dingtianhong@huawei.com
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1609021436160.5647@nanos
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/irq/chip.c | 18 | 
1 files changed, 14 insertions, 4 deletions
| diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index b4c1bc7c9ca2..93c373a8b12b 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -756,7 +756,6 @@ void handle_percpu_devid_irq(struct irq_desc *desc)  {  	struct irq_chip *chip = irq_desc_get_chip(desc);  	struct irqaction *action = desc->action; -	void *dev_id = raw_cpu_ptr(action->percpu_dev_id);  	unsigned int irq = irq_desc_get_irq(desc);  	irqreturn_t res; @@ -765,9 +764,20 @@ void handle_percpu_devid_irq(struct irq_desc *desc)  	if (chip->irq_ack)  		chip->irq_ack(&desc->irq_data); -	trace_irq_handler_entry(irq, action); -	res = action->handler(irq, dev_id); -	trace_irq_handler_exit(irq, action, res); +	if (likely(action)) { +		trace_irq_handler_entry(irq, action); +		res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id)); +		trace_irq_handler_exit(irq, action, res); +	} else { +		unsigned int cpu = smp_processor_id(); +		bool enabled = cpumask_test_cpu(cpu, desc->percpu_enabled); + +		if (enabled) +			irq_percpu_disable(desc, cpu); + +		pr_err_once("Spurious%s percpu IRQ%u on CPU%u\n", +			    enabled ? " and unmasked" : "", irq, cpu); +	}  	if (chip->irq_eoi)  		chip->irq_eoi(&desc->irq_data); | 
