On Thu, Jan 21, 2016 at 06:40:45AM -0500, Wenbo Wang wrote:
> From: Wenbo Wang <wenbo.w...@memblaze.com>
>
> [v3] Do request irq in nvme_init_queue() to handle request irq failures
>
> There is one problem with the original patch. Since init queue happens
> before request irq, online_queue might be left increased if request irq
> fails. This version merges request irq into nvme_init_queue() because:
> 1. It solves the online_queue counting issue if request irq fails.
> 2. nvme_init_queue() is always followed by request irq, this change
> simplifies code.
>
> This version also solves another possible race condition by moving
> adminq free irq before iounmap.
>
> [v2] Remove duplicate init code in nvme_alloc_queue()
>
> During reset process, the nvme_dev->bar (ioremapped) may change,
> so nvmeq->q_db shall be also updated by nvme_init_queue().
>
> [v1]
>
> Currently nvmeq irq is enabled before queue init, so a spurious
> interrupt triggered nvme_process_cq may access nvmeq->q_db just
> before it is updated, this could cause kernel panic.
>
> Signed-off-by: Wenbo Wang <wenbo.w...@memblaze.com>
> Reviewed-by: Wenwei Tao <wenwei....@memblaze.com>
> CC: sta...@vger.kernel.org
> ---
> drivers/nvme/host/pci.c | 38 ++++++++++++++++++++++++--------------
> 1 file changed, 24 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index f5c0e26..11e7cb6 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -1529,9 +1529,6 @@ static struct nvme_queue *nvme_alloc_queue(struct
> nvme_dev *dev, int qid,
> snprintf(nvmeq->irqname, sizeof(nvmeq->irqname), "nvme%dq%d",
> dev->instance, qid);
> spin_lock_init(&nvmeq->q_lock);
> - nvmeq->cq_head = 0;
> - nvmeq->cq_phase = 1;
> - nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
> nvmeq->q_depth = depth;
> nvmeq->qid = qid;
> nvmeq->cq_vector = -1;
> @@ -1562,8 +1559,9 @@ static int queue_request_irq(struct nvme_dev *dev,
> struct nvme_queue *nvmeq,
> IRQF_SHARED, name, nvmeq);
> }
>
> -static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
> +static int nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
> {
> + int result;
> struct nvme_dev *dev = nvmeq->dev;
>
> spin_lock_irq(&nvmeq->q_lock);
> @@ -1574,6 +1572,16 @@ static void nvme_init_queue(struct nvme_queue *nvmeq,
> u16 qid)
> memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth));
> dev->online_queues++;
> spin_unlock_irq(&nvmeq->q_lock);
> +
> + result = queue_request_irq(dev, nvmeq, nvmeq->irqname);
> +
> + if (result) {
> + spin_lock_irq(&nvmeq->q_lock);
> + nvmeq->cq_vector = -1;
> + dev->online_queues--;
> + spin_unlock_irq(&nvmeq->q_lock);
> + }
> + return result;
> }
>
> static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
> @@ -1590,11 +1598,15 @@ static int nvme_create_queue(struct nvme_queue
> *nvmeq, int qid)
> if (result < 0)
> goto release_cq;
>
> - result = queue_request_irq(dev, nvmeq, nvmeq->irqname);
> + /*
> + * Init queue door bell ioremap address before enabling irq, if not,
> + * a spurious interrupt triggered nvme_process_cq may access invalid
> + * address
> + */
> + result = nvme_init_queue(nvmeq, qid);
> if (result < 0)
> goto release_sq;
>
> - nvme_init_queue(nvmeq, qid);
> return result;
>
> release_sq:
> @@ -1790,11 +1802,9 @@ static int nvme_configure_admin_queue(struct nvme_dev
> *dev)
> goto free_nvmeq;
>
> nvmeq->cq_vector = 0;
> - result = queue_request_irq(dev, nvmeq, nvmeq->irqname);
> - if (result) {
> - nvmeq->cq_vector = -1;
> + result = nvme_init_queue(nvmeq, 0);
> + if (result)
> goto free_nvmeq;
> - }
>
> return result;
>
> @@ -2446,6 +2456,9 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
> nvme_release_cmb(dev);
> }
>
> + /* Deregister the admin queue's interrupt */
> + free_irq(dev->entry[0].vector, adminq);
> +
> size = db_bar_size(dev, nr_io_queues);
> if (size > 8192) {
> iounmap(dev->bar);
> @@ -2461,9 +2474,6 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
> adminq->q_db = dev->dbs;
> }
>
> - /* Deregister the admin queue's interrupt */
> - free_irq(dev->entry[0].vector, adminq);
> -
> /*
> * If we enable msix early due to not intx, disable it again before
> * setting up the full range we need.
> @@ -2496,6 +2506,7 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
> result = queue_request_irq(dev, adminq, adminq->irqname);
> if (result) {
> adminq->cq_vector = -1;
> + dev->online_queues--;
> goto free_queues;
> }
>
> @@ -3164,7 +3175,6 @@ static void nvme_probe_work(struct work_struct *work)
> goto disable;
> }
>
> - nvme_init_queue(dev->queues[0], 0);
> result = nvme_alloc_admin_tags(dev);
> if (result)
> goto disable;
> --
> 1.8.3.1
>
>
>
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Reviewed-by: Johannes Thumshirn <jthumsh...@suse.de>
--
Johannes Thumshirn Storage
jthumsh...@suse.de +49 911 74053 689
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