From 949928c1c731417cc0f070912c63878b62b544f4 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Thu, 17 Dec 2015 17:08:15 -0700 Subject: [PATCH] NVMe: Fix possible queue use after freed This notifies blk-mq when the tag set contains a different number of queues prior to freeing unused ones that the request queue points to. Signed-off-by: Keith Busch Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/nvme/host/pci.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 72ef8322d32a..08791338ce75 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1381,7 +1381,7 @@ static int nvme_kthread(void *data) static int nvme_create_io_queues(struct nvme_dev *dev) { - unsigned i; + unsigned i, max; int ret = 0; for (i = dev->queue_count; i <= dev->max_qid; i++) { @@ -1391,7 +1391,8 @@ static int nvme_create_io_queues(struct nvme_dev *dev) } } - for (i = dev->online_queues; i <= dev->queue_count - 1; i++) { + max = min(dev->max_qid, dev->queue_count - 1); + for (i = dev->online_queues; i <= max; i++) { ret = nvme_create_queue(dev->queues[i], i); if (ret) { nvme_free_queues(dev, i); @@ -1548,9 +1549,6 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) adminq->cq_vector = -1; goto free_queues; } - - /* Free previously allocated queues that are no longer usable */ - nvme_free_queues(dev, nr_io_queues + 1); return nvme_create_io_queues(dev); free_queues: @@ -1684,7 +1682,13 @@ static int nvme_dev_add(struct nvme_dev *dev) if (blk_mq_alloc_tag_set(&dev->tagset)) return 0; dev->ctrl.tagset = &dev->tagset; + } else { + blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1); + + /* Free previously allocated queues that are no longer usable */ + nvme_free_queues(dev, dev->online_queues); } + queue_work(nvme_workq, &dev->scan_work); return 0; } -- 2.20.1