From a6b3a3fa042343e29ffaf9169f5ba3c819d4f9a2 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Oct 2018 15:41:00 +0000 Subject: net: mvpp2: Fix affinity hint allocation The mvpp2 driver has the curious behaviour of passing a stack variable to irq_set_affinity_hint(), which results in the kernel exploding the first time anyone accesses this information. News flash: userspace does, and irqbalance will happily take the machine down. Great stuff. An easy fix is to track the mask within the queue_vector structure, and to make sure it has the same lifetime as the interrupt itself. Fixes: e531f76757eb ("net: mvpp2: handle cases where more CPUs are available than s/w threads") Signed-off-by: Marc Zyngier Signed-off-by: David S. Miller --- drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) (limited to 'drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c') diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c index 14f9679c957c..7a37a37e3fb3 100644 --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c @@ -3298,24 +3298,30 @@ static int mvpp2_irqs_init(struct mvpp2_port *port) for (i = 0; i < port->nqvecs; i++) { struct mvpp2_queue_vector *qv = port->qvecs + i; - if (qv->type == MVPP2_QUEUE_VECTOR_PRIVATE) + if (qv->type == MVPP2_QUEUE_VECTOR_PRIVATE) { + qv->mask = kzalloc(cpumask_size(), GFP_KERNEL); + if (!qv->mask) { + err = -ENOMEM; + goto err; + } + irq_set_status_flags(qv->irq, IRQ_NO_BALANCING); + } err = request_irq(qv->irq, mvpp2_isr, 0, port->dev->name, qv); if (err) goto err; if (qv->type == MVPP2_QUEUE_VECTOR_PRIVATE) { - unsigned long mask = 0; unsigned int cpu; for_each_present_cpu(cpu) { if (mvpp2_cpu_to_thread(port->priv, cpu) == qv->sw_thread_id) - mask |= BIT(cpu); + cpumask_set_cpu(cpu, qv->mask); } - irq_set_affinity_hint(qv->irq, to_cpumask(&mask)); + irq_set_affinity_hint(qv->irq, qv->mask); } } @@ -3325,6 +3331,8 @@ err: struct mvpp2_queue_vector *qv = port->qvecs + i; irq_set_affinity_hint(qv->irq, NULL); + kfree(qv->mask); + qv->mask = NULL; free_irq(qv->irq, qv); } @@ -3339,6 +3347,8 @@ static void mvpp2_irqs_deinit(struct mvpp2_port *port) struct mvpp2_queue_vector *qv = port->qvecs + i; irq_set_affinity_hint(qv->irq, NULL); + kfree(qv->mask); + qv->mask = NULL; irq_clear_status_flags(qv->irq, IRQ_NO_BALANCING); free_irq(qv->irq, qv); } -- cgit v1.2.3-59-g8ed1b