From: Marc Zyngier <marc.zyngier@arm.com>
To: davem@davemloft.net, Antoine Tenart <antoine.tenart@bootlin.com>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
thomas.petazzoni@bootlin.com, maxime.chevallier@bootlin.com,
miquel.raynal@bootlin.com, gregory.clement@bootlin.com,
nadavh@marvell.com, stefanc@marvell.com, ymarkman@marvell.com,
mw@semihalf.com
Subject: [PATCH] net: mvpp2: Fix affinity hint allocation
Date: Tue, 30 Oct 2018 15:41:00 +0000 [thread overview]
Message-ID: <20181030154100.78512-1-marc.zyngier@arm.com> (raw)
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 <marc.zyngier@arm.com>
---
As requested in https://lore.kernel.org/lkml/20181030135354.GD3407@kwain/
drivers/net/ethernet/marvell/mvpp2/mvpp2.h | 1 +
.../net/ethernet/marvell/mvpp2/mvpp2_main.c | 18 ++++++++++++++----
2 files changed, 15 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
index 176c6b56fdcc..398328f10743 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
@@ -796,6 +796,7 @@ struct mvpp2_queue_vector {
int nrxqs;
u32 pending_cause_rx;
struct mvpp2_port *port;
+ struct cpumask *mask;
};
struct mvpp2_port {
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 @@ static int mvpp2_irqs_init(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;
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);
}
--
2.19.1
next reply other threads:[~2018-10-30 15:41 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-30 15:41 Marc Zyngier [this message]
2018-10-30 18:40 ` [PATCH] net: mvpp2: Fix affinity hint allocation David Miller
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