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. Cc: stable@xxxxxxxxxxxxxxx Cc: <stable@xxxxxxxxxxxxxxx> # 4.0.x- Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxx> --- drivers/block/nvme-core.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c index e23be20..28da73c 100644 --- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -597,6 +597,7 @@ static void req_completion(struct nvme_queue *nvmeq, void *ctx, 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; @@ -605,12 +606,13 @@ static void req_completion(struct nvme_queue *nvmeq, void *ctx, && (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 @@ -620,7 +622,7 @@ static void req_completion(struct nvme_queue *nvmeq, void *ctx, 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); @@ -633,7 +635,8 @@ static void req_completion(struct nvme_queue *nvmeq, void *ctx, } 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. */ -- 2.6.2.307.g37023ba -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html