| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.1 79/86] NVMe: Fix memory leak on retried commands | Date | Fri, 6 Nov 2015 11:23:18 -0800 |
| |
4.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Keith Busch <keith.busch@intel.com>
commit 0dfc70c33409afc232ef0b9ec210535dfbf9bc61 upstream.
Resources are reallocated for requeued commands, so unmap and release the iod for the failed command.
It's a pretty bad memory leak and causes a kernel hang if you remove a drive because of a busy dma pool. You'll get messages spewing like this:
nvme 0000:xx:xx.x: dma_pool_destroy prp list 256, ffff880420dec000 busy
and lock up pci and the driver since removal never completes while holding a lock.
Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- drivers/block/nvme-core.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
--- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -590,6 +590,7 @@ static void req_completion(struct nvme_q struct nvme_iod *iod = ctx; struct request *req = iod_get_private(iod); struct nvme_cmd_info *cmd_rq = blk_mq_rq_to_pdu(req); + bool requeue = false; u16 status = le16_to_cpup(&cqe->status) >> 1; @@ -598,12 +599,13 @@ static void req_completion(struct nvme_q && (jiffies - req->start_time) < req->timeout) { unsigned long flags; + requeue = true; blk_mq_requeue_request(req); spin_lock_irqsave(req->q->queue_lock, flags); if (!blk_queue_stopped(req->q)) blk_mq_kick_requeue_list(req->q); spin_unlock_irqrestore(req->q->queue_lock, flags); - return; + goto release_iod; } req->errors = nvme_error_status(status); } else @@ -613,7 +615,7 @@ static void req_completion(struct nvme_q dev_warn(&nvmeq->dev->pci_dev->dev, "completing aborted command with status:%04x\n", status); - + release_iod: if (iod->nents) { dma_unmap_sg(&nvmeq->dev->pci_dev->dev, iod->sg, iod->nents, rq_data_dir(req) ? DMA_TO_DEVICE : DMA_FROM_DEVICE); @@ -626,7 +628,8 @@ static void req_completion(struct nvme_q } nvme_free_iod(nvmeq->dev, iod); - blk_mq_complete_request(req); + if (likely(!requeue)) + blk_mq_complete_request(req); } /* length is in bytes. gfp flags indicates whether we may sleep. */
|