3 files changed, 33 insertions, 13 deletions

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index fc13a10eb901..d31d8e252578 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1393,11 +1393,9 @@ static inline void nvme_release_cmb(struct nvme_dev *dev)
 	if (dev->cmb) {
 		iounmap(dev->cmb);
 		dev->cmb = NULL;
-		if (dev->cmbsz) {
-			sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
-						     &dev_attr_cmb.attr, NULL);
-			dev->cmbsz = 0;
-		}
+		sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
+					     &dev_attr_cmb.attr, NULL);
+		dev->cmbsz = 0;
 	}
 }
 
@@ -1632,16 +1630,14 @@ static int nvme_pci_enable(struct nvme_dev *dev)
 
 	/*
 	 * CMBs can currently only exist on >=1.2 PCIe devices. We only
-	 * populate sysfs if a CMB is implemented. Note that we add the
-	 * CMB attribute to the nvme_ctrl kobj which removes the need to remove
-	 * it on exit. Since nvme_dev_attrs_group has no name we can pass
-	 * NULL as final argument to sysfs_add_file_to_group.
+	 * populate sysfs if a CMB is implemented. Since nvme_dev_attrs_group
+	 * has no name we can pass NULL as final argument to
+	 * sysfs_add_file_to_group.
 	 */
 
 	if (readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 2, 0)) {
 		dev->cmb = nvme_map_cmb(dev);
-
-		if (dev->cmbsz) {
+		if (dev->cmb) {
 			if (sysfs_add_file_to_group(&dev->ctrl.device->kobj,
 						    &dev_attr_cmb.attr, NULL))
 				dev_warn(dev->dev,
diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 2caed285fd7b..cdb7752dcbb7 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -192,6 +192,7 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
 	id->vid = 0;
 	id->ssvid = 0;
 
+	memset(id->sn, ' ', sizeof(id->sn));
 	bin2hex(id->sn, &ctrl->subsys->serial,
 		min(sizeof(ctrl->subsys->serial), sizeof(id->sn) / 2));
 	copy_and_pad(id->mn, sizeof(id->mn), model, sizeof(model) - 1);
diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c
index 53bd32550867..2dfd877974d7 100644
--- a/drivers/nvme/target/rdma.c
+++ b/drivers/nvme/target/rdma.c
@@ -65,6 +65,7 @@ struct nvmet_rdma_rsp {
 
 	struct nvmet_req	req;
 
+	bool			allocated;
 	u8			n_rdma;
 	u32			flags;
 	u32			invalidate_rkey;
@@ -167,11 +168,19 @@ nvmet_rdma_get_rsp(struct nvmet_rdma_queue *queue)
 	unsigned long flags;
 
 	spin_lock_irqsave(&queue->rsps_lock, flags);
-	rsp = list_first_entry(&queue->free_rsps,
+	rsp = list_first_entry_or_null(&queue->free_rsps,
 				struct nvmet_rdma_rsp, free_list);
-	list_del(&rsp->free_list);
+	if (likely(rsp))
+		list_del(&rsp->free_list);
 	spin_unlock_irqrestore(&queue->rsps_lock, flags);
 
+	if (unlikely(!rsp)) {
+		rsp = kmalloc(sizeof(*rsp), GFP_KERNEL);
+		if (unlikely(!rsp))
+			return NULL;
+		rsp->allocated = true;
+	}
+
 	return rsp;
 }
 
@@ -180,6 +189,11 @@ nvmet_rdma_put_rsp(struct nvmet_rdma_rsp *rsp)
 {
 	unsigned long flags;
 
+	if (rsp->allocated) {
+		kfree(rsp);
+		return;
+	}
+
 	spin_lock_irqsave(&rsp->queue->rsps_lock, flags);
 	list_add_tail(&rsp->free_list, &rsp->queue->free_rsps);
 	spin_unlock_irqrestore(&rsp->queue->rsps_lock, flags);
@@ -755,6 +769,15 @@ static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc)
 
 	cmd->queue = queue;
 	rsp = nvmet_rdma_get_rsp(queue);
+	if (unlikely(!rsp)) {
+		/*
+		 * we get here only under memory pressure,
+		 * silently drop and have the host retry
+		 * as we can't even fail it.
+		 */
+		nvmet_rdma_post_recv(queue->dev, cmd);
+		return;
+	}
 	rsp->queue = queue;
 	rsp->cmd = cmd;
 	rsp->flags = 0;