From b5875222de2fb91339db79a753677ba4f68120d0 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Fri, 11 Dec 2015 13:14:28 -0700 Subject: [PATCH] NVMe: IO ending fixes on surprise removal This patch fixes a lost request discovered during IO + hot removal. The driver's pci removal deletes gendisks prior to shutting down the controller to allow dirty data to sync. Dirty data can not be synced on a surprise removal, though, and would potentially block indefinitely. The driver previously had marked the queue as dying in this scenario to prevent new requests from attempting, however it will still block for requests that already entered the queue. This patch fixes this by quiescing IO first, then aborting the requeued requests before deleting disks. Reported-by: Sujith Pandel Signed-off-by: Keith Busch Tested-by: Sujith Pandel Signed-off-by: Jens Axboe --- drivers/nvme/host/pci.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 9e294ff4e652..0c67b57be83c 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -2540,8 +2540,17 @@ static void nvme_ns_remove(struct nvme_ns *ns) { bool kill = nvme_io_incapable(ns->dev) && !blk_queue_dying(ns->queue); - if (kill) + if (kill) { blk_set_queue_dying(ns->queue); + + /* + * The controller was shutdown first if we got here through + * device removal. The shutdown may requeue outstanding + * requests. These need to be aborted immediately so + * del_gendisk doesn't block indefinitely for their completion. + */ + blk_mq_abort_requeue_list(ns->queue); + } if (ns->disk->flags & GENHD_FL_UP) del_gendisk(ns->disk); if (kill || !blk_queue_dying(ns->queue)) { @@ -2977,6 +2986,15 @@ static void nvme_dev_remove(struct nvme_dev *dev) { struct nvme_ns *ns, *next; + if (nvme_io_incapable(dev)) { + /* + * If the device is not capable of IO (surprise hot-removal, + * for example), we need to quiesce prior to deleting the + * namespaces. This will end outstanding requests and prevent + * attempts to sync dirty data. + */ + nvme_dev_shutdown(dev); + } list_for_each_entry_safe(ns, next, &dev->namespaces, list) nvme_ns_remove(ns); }