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 | |
| parent | genirq: Fix missing irq allocation affinity hint (diff) | |
| download | linux-fc590c22f9f056ab50190b797f6cacead29f9b75.tar.xz linux-fc590c22f9f056ab50190b797f6cacead29f9b75.zip | |
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
| -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); |