[PATCHv2] NVMe: Fix double free irq

[Keith Busch]

Sets the vector to an invalid value after it's freed so we don't free
it twice.

Signed-off-by: Keith Busch <keith.busch at intel.com>
---
Obsoletes this one:

  http://lists.infradead.org/pipermail/linux-nvme/2014-December/001356.html

v1->v2:
  Fixed struct alignment, verified with 'pahole'.
  Fixed initial setting of IO queue cq_vector to before creating the cq.

 drivers/block/nvme-core.c |   19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index aa6be45..6c4c628 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -105,8 +105,8 @@ struct nvme_queue {
 	dma_addr_t sq_dma_addr;
 	dma_addr_t cq_dma_addr;
 	u32 __iomem *q_db;
+	int cq_vector;
 	u16 q_depth;
-	u16 cq_vector;
 	u16 sq_head;
 	u16 sq_tail;
 	u16 cq_head;
@@ -1131,10 +1131,16 @@ static void nvme_free_queues(struct nvme_dev *dev, int lowest)
  */
 static int nvme_suspend_queue(struct nvme_queue *nvmeq)
 {
-	int vector = nvmeq->dev->entry[nvmeq->cq_vector].vector;
+	int vector;
 
 	spin_lock_irq(&nvmeq->q_lock);
+	if (nvmeq->cq_vector == -1) {
+		spin_unlock_irq(&nvmeq->q_lock);
+		return 1;
+	}
+	vector = nvmeq->dev->entry[nvmeq->cq_vector].vector;
 	nvmeq->dev->online_queues--;
+	nvmeq->cq_vector = -1;
 	spin_unlock_irq(&nvmeq->q_lock);
 
 	irq_set_affinity_hint(vector, NULL);
@@ -1173,7 +1179,7 @@ static void nvme_disable_queue(struct nvme_dev *dev, int qid)
 }
 
 static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
-							int depth, int vector)
+							int depth)
 {
 	struct device *dmadev = &dev->pci_dev->dev;
 	struct nvme_queue *nvmeq = kzalloc(sizeof(*nvmeq), GFP_KERNEL);
@@ -1199,7 +1205,6 @@ static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
 	nvmeq->cq_phase = 1;
 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
 	nvmeq->q_depth = depth;
-	nvmeq->cq_vector = vector;
 	nvmeq->qid = qid;
 	dev->queue_count++;
 	dev->queues[qid] = nvmeq;
@@ -1244,6 +1249,7 @@ static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
 	struct nvme_dev *dev = nvmeq->dev;
 	int result;
 
+	nvmeq->cq_vector = qid - 1;
 	result = adapter_alloc_cq(dev, qid, nvmeq);
 	if (result < 0)
 		return result;
@@ -1416,7 +1422,7 @@ static int nvme_configure_admin_queue(struct nvme_dev *dev)
 
 	nvmeq = dev->queues[0];
 	if (!nvmeq) {
-		nvmeq = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH, 0);
+		nvmeq = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH);
 		if (!nvmeq)
 			return -ENOMEM;
 	}
@@ -1443,6 +1449,7 @@ static int nvme_configure_admin_queue(struct nvme_dev *dev)
 	if (result)
 		goto free_nvmeq;
 
+	nvmeq->cq_vector = 0;
 	result = queue_request_irq(dev, nvmeq, nvmeq->irqname);
 	if (result)
 		goto free_tags;
@@ -1944,7 +1951,7 @@ static void nvme_create_io_queues(struct nvme_dev *dev)
 	unsigned i;
 
 	for (i = dev->queue_count; i <= dev->max_qid; i++)
-		if (!nvme_alloc_queue(dev, i, dev->q_depth, i - 1))
+		if (!nvme_alloc_queue(dev, i, dev->q_depth))
 			break;
 
 	for (i = dev->online_queues; i <= dev->queue_count - 1; i++)
-- 
1.7.10.4