Merge tag 'for-linus-20180511' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Just a few NVMe fixes this round - one fixing a use-after-free, one
  fixes the return value after controller reset, and the last one fixes
  an issue where some drives will spuriously EIO. We should get these
  into 4.17"

* tag 'for-linus-20180511' of git://git.kernel.dk/linux-block:
  nvme: add quirk to force medium priority for SQ creation
  nvme: Fix sync controller reset return
  nvme: fix use-after-free in nvme_free_ns_head

Author: torvalds

drivers/nvme/host/core.c

@@ -99,6 +99,7 @@ static struct class *nvme_subsys_class;
 
 static void nvme_ns_remove(struct nvme_ns *ns);
 static int nvme_revalidate_disk(struct gendisk *disk);
+static void nvme_put_subsystem(struct nvme_subsystem *subsys);
 
 int nvme_reset_ctrl(struct nvme_ctrl *ctrl)
 {
@@ -117,7 +118,8 @@ int nvme_reset_ctrl_sync(struct nvme_ctrl *ctrl)
 	ret = nvme_reset_ctrl(ctrl);
 	if (!ret) {
 		flush_work(&ctrl->reset_work);
-		if (ctrl->state != NVME_CTRL_LIVE)
+		if (ctrl->state != NVME_CTRL_LIVE &&
+		    ctrl->state != NVME_CTRL_ADMIN_ONLY)
 			ret = -ENETRESET;
 	}
 
@@ -350,6 +352,7 @@ static void nvme_free_ns_head(struct kref *ref)
 	ida_simple_remove(&head->subsys->ns_ida, head->instance);
 	list_del_init(&head->entry);
 	cleanup_srcu_struct(&head->srcu);
+	nvme_put_subsystem(head->subsys);
 	kfree(head);
 }
 
@@ -2861,6 +2864,9 @@ static struct nvme_ns_head *nvme_alloc_ns_head(struct nvme_ctrl *ctrl,
 		goto out_cleanup_srcu;
 
 	list_add_tail(&head->entry, &ctrl->subsys->nsheads);
+
+	kref_get(&ctrl->subsys->ref);
+
 	return head;
 out_cleanup_srcu:
 	cleanup_srcu_struct(&head->srcu);

drivers/nvme/host/nvme.h

@@ -84,6 +84,11 @@ enum nvme_quirks {
 	 * Supports the LighNVM command set if indicated in vs[1].
 	 */
 	NVME_QUIRK_LIGHTNVM			= (1 << 6),
+
+	/*
+	 * Set MEDIUM priority on SQ creation
+	 */
+	NVME_QUIRK_MEDIUM_PRIO_SQ		= (1 << 7),
 };
 
 /*

drivers/nvme/host/pci.c

@@ -1093,9 +1093,18 @@ static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
 static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
 						struct nvme_queue *nvmeq)
 {
+	struct nvme_ctrl *ctrl = &dev->ctrl;
 	struct nvme_command c;
 	int flags = NVME_QUEUE_PHYS_CONTIG;
 
+	/*
+	 * Some drives have a bug that auto-enables WRRU if MEDIUM isn't
+	 * set. Since URGENT priority is zeroes, it makes all queues
+	 * URGENT.
+	 */
+	if (ctrl->quirks & NVME_QUIRK_MEDIUM_PRIO_SQ)
+		flags |= NVME_SQ_PRIO_MEDIUM;
+
 	/*
 	 * Note: we (ab)use the fact that the prp fields survive if no data
 	 * is attached to the request.
@@ -2701,7 +2710,8 @@ static const struct pci_device_id nvme_id_table[] = {
 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
 				NVME_QUIRK_DEALLOCATE_ZEROES, },
 	{ PCI_VDEVICE(INTEL, 0xf1a5),	/* Intel 600P/P3100 */
-		.driver_data = NVME_QUIRK_NO_DEEPEST_PS },
+		.driver_data = NVME_QUIRK_NO_DEEPEST_PS |
+				NVME_QUIRK_MEDIUM_PRIO_SQ },
 	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
 		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
 	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */