Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

A function in kernel/bpf/syscall.c which got a bug fix in 'net'
was moved to kernel/bpf/verifier.c in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>

28 files changed, 288 insertions, 199 deletions

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 662036bdc65e..c8ea9d698cd0 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -1617,7 +1617,11 @@ static int cmp_map(const void *m0, const void *m1)
 	const struct nfit_set_info_map *map0 = m0;
 	const struct nfit_set_info_map *map1 = m1;
 
-	return map0->region_offset - map1->region_offset;
+	if (map0->region_offset < map1->region_offset)
+		return -1;
+	else if (map0->region_offset > map1->region_offset)
+		return 1;
+	return 0;
 }
 
 /* Retrieve the nth entry referencing this spa */
diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig
index 3e2ab3b14eea..9e95bf94eb13 100644
--- a/drivers/dax/Kconfig
+++ b/drivers/dax/Kconfig
@@ -2,6 +2,7 @@ menuconfig DEV_DAX
 	tristate "DAX: direct access to differentiated memory"
 	default m if NVDIMM_DAX
 	depends on TRANSPARENT_HUGEPAGE
+	select SRCU
 	help
 	  Support raw access to differentiated (persistence, bandwidth,
 	  latency...) memory via an mmap(2) capable character
diff --git a/drivers/dax/dax.c b/drivers/dax/dax.c
index 80c6db279ae1..806f180c80d8 100644
--- a/drivers/dax/dax.c
+++ b/drivers/dax/dax.c
@@ -25,6 +25,7 @@
 #include "dax.h"
 
 static dev_t dax_devt;
+DEFINE_STATIC_SRCU(dax_srcu);
 static struct class *dax_class;
 static DEFINE_IDA(dax_minor_ida);
 static int nr_dax = CONFIG_NR_DEV_DAX;
@@ -60,7 +61,7 @@ struct dax_region {
  * @region - parent region
  * @dev - device backing the character device
  * @cdev - core chardev data
- * @alive - !alive + rcu grace period == no new mappings can be established
+ * @alive - !alive + srcu grace period == no new mappings can be established
  * @id - child id in the region
  * @num_resources - number of physical address extents in this device
  * @res - array of physical address ranges
@@ -569,7 +570,7 @@ static int __dax_dev_pud_fault(struct dax_dev *dax_dev, struct vm_fault *vmf)
 static int dax_dev_huge_fault(struct vm_fault *vmf,
 		enum page_entry_size pe_size)
 {
-	int rc;
+	int rc, id;
 	struct file *filp = vmf->vma->vm_file;
 	struct dax_dev *dax_dev = filp->private_data;
 
@@ -578,7 +579,7 @@ static int dax_dev_huge_fault(struct vm_fault *vmf,
 			? "write" : "read",
 			vmf->vma->vm_start, vmf->vma->vm_end);
 
-	rcu_read_lock();
+	id = srcu_read_lock(&dax_srcu);
 	switch (pe_size) {
 	case PE_SIZE_PTE:
 		rc = __dax_dev_pte_fault(dax_dev, vmf);
@@ -592,7 +593,7 @@ static int dax_dev_huge_fault(struct vm_fault *vmf,
 	default:
 		return VM_FAULT_FALLBACK;
 	}
-	rcu_read_unlock();
+	srcu_read_unlock(&dax_srcu, id);
 
 	return rc;
 }
@@ -713,11 +714,11 @@ static void unregister_dax_dev(void *dev)
 	 * Note, rcu is not protecting the liveness of dax_dev, rcu is
 	 * ensuring that any fault handlers that might have seen
 	 * dax_dev->alive == true, have completed.  Any fault handlers
-	 * that start after synchronize_rcu() has started will abort
+	 * that start after synchronize_srcu() has started will abort
 	 * upon seeing dax_dev->alive == false.
 	 */
 	dax_dev->alive = false;
-	synchronize_rcu();
+	synchronize_srcu(&dax_srcu);
 	unmap_mapping_range(dax_dev->inode->i_mapping, 0, 0, 1);
 	cdev_del(cdev);
 	device_unregister(dev);
diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
index 64a1095e4d14..a0ca68ce3fbb 100644
--- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
+++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
@@ -134,6 +134,7 @@ static void set_max_bgx_per_node(struct pci_dev *pdev)
 	pci_read_config_word(pdev, PCI_SUBSYSTEM_ID, &sdevid);
 	switch (sdevid) {
 	case PCI_SUBSYS_DEVID_81XX_BGX:
+	case PCI_SUBSYS_DEVID_81XX_RGX:
 		max_bgx_per_node = MAX_BGX_PER_CN81XX;
 		break;
 	case PCI_SUBSYS_DEVID_83XX_BGX:
diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.h b/drivers/net/ethernet/cavium/thunder/thunder_bgx.h
index c5080f2cead5..6b7fe6fdd13b 100644
--- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.h
+++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.h
@@ -16,6 +16,7 @@
 /* Subsystem device IDs */
 #define PCI_SUBSYS_DEVID_88XX_BGX		0xA126
 #define PCI_SUBSYS_DEVID_81XX_BGX		0xA226
+#define PCI_SUBSYS_DEVID_81XX_RGX		0xA254
 #define PCI_SUBSYS_DEVID_83XX_BGX		0xA326
 
 #define    MAX_BGX_THUNDER			8 /* Max 2 nodes, 4 per node */
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index d81d3b6dfd87..16f97552ae98 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -613,7 +613,7 @@ static int mtk_tx_map(struct sk_buff *skb, struct net_device *dev,
 	struct mtk_mac *mac = netdev_priv(dev);
 	struct mtk_eth *eth = mac->hw;
 	struct mtk_tx_dma *itxd, *txd;
-	struct mtk_tx_buf *tx_buf;
+	struct mtk_tx_buf *itx_buf, *tx_buf;
 	dma_addr_t mapped_addr;
 	unsigned int nr_frags;
 	int i, n_desc = 1;
@@ -627,8 +627,8 @@ static int mtk_tx_map(struct sk_buff *skb, struct net_device *dev,
 	fport = (mac->id + 1) << TX_DMA_FPORT_SHIFT;
 	txd4 |= fport;
 
-	tx_buf = mtk_desc_to_tx_buf(ring, itxd);
-	memset(tx_buf, 0, sizeof(*tx_buf));
+	itx_buf = mtk_desc_to_tx_buf(ring, itxd);
+	memset(itx_buf, 0, sizeof(*itx_buf));
 
 	if (gso)
 		txd4 |= TX_DMA_TSO;
@@ -647,9 +647,11 @@ static int mtk_tx_map(struct sk_buff *skb, struct net_device *dev,
 		return -ENOMEM;
 
 	WRITE_ONCE(itxd->txd1, mapped_addr);
-	tx_buf->flags |= MTK_TX_FLAGS_SINGLE0;
-	dma_unmap_addr_set(tx_buf, dma_addr0, mapped_addr);
-	dma_unmap_len_set(tx_buf, dma_len0, skb_headlen(skb));
+	itx_buf->flags |= MTK_TX_FLAGS_SINGLE0;
+	itx_buf->flags |= (!mac->id) ? MTK_TX_FLAGS_FPORT0 :
+			  MTK_TX_FLAGS_FPORT1;
+	dma_unmap_addr_set(itx_buf, dma_addr0, mapped_addr);
+	dma_unmap_len_set(itx_buf, dma_len0, skb_headlen(skb));
 
 	/* TX SG offload */
 	txd = itxd;
@@ -685,11 +687,13 @@ static int mtk_tx_map(struct sk_buff *skb, struct net_device *dev,
 					       last_frag * TX_DMA_LS0));
 			WRITE_ONCE(txd->txd4, fport);
 
-			tx_buf->skb = (struct sk_buff *)MTK_DMA_DUMMY_DESC;
 			tx_buf = mtk_desc_to_tx_buf(ring, txd);
 			memset(tx_buf, 0, sizeof(*tx_buf));
-
+			tx_buf->skb = (struct sk_buff *)MTK_DMA_DUMMY_DESC;
 			tx_buf->flags |= MTK_TX_FLAGS_PAGE0;
+			tx_buf->flags |= (!mac->id) ? MTK_TX_FLAGS_FPORT0 :
+					 MTK_TX_FLAGS_FPORT1;
+
 			dma_unmap_addr_set(tx_buf, dma_addr0, mapped_addr);
 			dma_unmap_len_set(tx_buf, dma_len0, frag_map_size);
 			frag_size -= frag_map_size;
@@ -698,7 +702,7 @@ static int mtk_tx_map(struct sk_buff *skb, struct net_device *dev,
 	}
 
 	/* store skb to cleanup */
-	tx_buf->skb = skb;
+	itx_buf->skb = skb;
 
 	WRITE_ONCE(itxd->txd4, txd4);
 	WRITE_ONCE(itxd->txd3, (TX_DMA_SWC | TX_DMA_PLEN0(skb_headlen(skb)) |
@@ -1012,17 +1016,16 @@ static int mtk_poll_tx(struct mtk_eth *eth, int budget)
 
 	while ((cpu != dma) && budget) {
 		u32 next_cpu = desc->txd2;
-		int mac;
+		int mac = 0;
 
 		desc = mtk_qdma_phys_to_virt(ring, desc->txd2);
 		if ((desc->txd3 & TX_DMA_OWNER_CPU) == 0)
 			break;
 
-		mac = (desc->txd4 >> TX_DMA_FPORT_SHIFT) &
-		       TX_DMA_FPORT_MASK;
-		mac--;
-
 		tx_buf = mtk_desc_to_tx_buf(ring, desc);
+		if (tx_buf->flags & MTK_TX_FLAGS_FPORT1)
+			mac = 1;
+
 		skb = tx_buf->skb;
 		if (!skb) {
 			condition = 1;
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
index 996024d02668..3c46a3b613b9 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -410,12 +410,18 @@ struct mtk_hw_stats {
 	struct u64_stats_sync	syncp;
 };
 
-/* PDMA descriptor can point at 1-2 segments. This enum allows us to track how
- * memory was allocated so that it can be freed properly
- */
 enum mtk_tx_flags {
+	/* PDMA descriptor can point at 1-2 segments. This enum allows us to
+	 * track how memory was allocated so that it can be freed properly.
+	 */
 	MTK_TX_FLAGS_SINGLE0	= 0x01,
 	MTK_TX_FLAGS_PAGE0	= 0x02,
+
+	/* MTK_TX_FLAGS_FPORTx allows tracking which port the transmitted
+	 * SKB out instead of looking up through hardware TX descriptor.
+	 */
+	MTK_TX_FLAGS_FPORT0	= 0x04,
+	MTK_TX_FLAGS_FPORT1	= 0x08,
 };
 
 /* This enum allows us to identify how the clock is defined on the array of the
diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index 54248775f227..f68c4db656ed 100644
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -1127,12 +1127,70 @@ static struct mdiobb_ops bb_ops = {
 	.get_mdio_data = sh_get_mdio,
 };
 
+/* free Tx skb function */
+static int sh_eth_tx_free(struct net_device *ndev, bool sent_only)
+{
+	struct sh_eth_private *mdp = netdev_priv(ndev);
+	struct sh_eth_txdesc *txdesc;
+	int free_num = 0;
+	int entry;
+	bool sent;
+
+	for (; mdp->cur_tx - mdp->dirty_tx > 0; mdp->dirty_tx++) {
+		entry = mdp->dirty_tx % mdp->num_tx_ring;
+		txdesc = &mdp->tx_ring[entry];
+		sent = !(txdesc->status & cpu_to_le32(TD_TACT));
+		if (sent_only && !sent)
+			break;
+		/* TACT bit must be checked before all the following reads */
+		dma_rmb();
+		netif_info(mdp, tx_done, ndev,
+			   "tx entry %d status 0x%08x\n",
+			   entry, le32_to_cpu(txdesc->status));
+		/* Free the original skb. */
+		if (mdp->tx_skbuff[entry]) {
+			dma_unmap_single(&ndev->dev, le32_to_cpu(txdesc->addr),
+					 le32_to_cpu(txdesc->len) >> 16,
+					 DMA_TO_DEVICE);
+			dev_kfree_skb_irq(mdp->tx_skbuff[entry]);
+			mdp->tx_skbuff[entry] = NULL;
+			free_num++;
+		}
+		txdesc->status = cpu_to_le32(TD_TFP);
+		if (entry >= mdp->num_tx_ring - 1)
+			txdesc->status |= cpu_to_le32(TD_TDLE);
+
+		if (sent) {
+			ndev->stats.tx_packets++;
+			ndev->stats.tx_bytes += le32_to_cpu(txdesc->len) >> 16;
+		}
+	}
+	return free_num;
+}
+
 /* free skb and descriptor buffer */
 static void sh_eth_ring_free(struct net_device *ndev)
 {
 	struct sh_eth_private *mdp = netdev_priv(ndev);
 	int ringsize, i;
 
+	if (mdp->rx_ring) {
+		for (i = 0; i < mdp->num_rx_ring; i++) {
+			if (mdp->rx_skbuff[i]) {
+				struct sh_eth_rxdesc *rxdesc = &mdp->rx_ring[i];
+
+				dma_unmap_single(&ndev->dev,
+						 le32_to_cpu(rxdesc->addr),
+						 ALIGN(mdp->rx_buf_sz, 32),
+						 DMA_FROM_DEVICE);
+			}
+		}
+		ringsize = sizeof(struct sh_eth_rxdesc) * mdp->num_rx_ring;
+		dma_free_coherent(NULL, ringsize, mdp->rx_ring,
+				  mdp->rx_desc_dma);
+		mdp->rx_ring = NULL;
+	}
+
 	/* Free Rx skb ringbuffer */
 	if (mdp->rx_skbuff) {
 		for (i = 0; i < mdp->num_rx_ring; i++)
@@ -1141,27 +1199,18 @@ static void sh_eth_ring_free(struct net_device *ndev)
 	kfree(mdp->rx_skbuff);
 	mdp->rx_skbuff = NULL;
 
-	/* Free Tx skb ringbuffer */
-	if (mdp->tx_skbuff) {
-		for (i = 0; i < mdp->num_tx_ring; i++)
-			dev_kfree_skb(mdp->tx_skbuff[i]);
-	}
-	kfree(mdp->tx_skbuff);
-	mdp->tx_skbuff = NULL;
-
-	if (mdp->rx_ring) {
-		ringsize = sizeof(struct sh_eth_rxdesc) * mdp->num_rx_ring;
-		dma_free_coherent(NULL, ringsize, mdp->rx_ring,
-				  mdp->rx_desc_dma);
-		mdp->rx_ring = NULL;
-	}
-
 	if (mdp->tx_ring) {
+		sh_eth_tx_free(ndev, false);
+
 		ringsize = sizeof(struct sh_eth_txdesc) * mdp->num_tx_ring;
 		dma_free_coherent(NULL, ringsize, mdp->tx_ring,
 				  mdp->tx_desc_dma);
 		mdp->tx_ring = NULL;
 	}
+
+	/* Free Tx skb ringbuffer */
+	kfree(mdp->tx_skbuff);
+	mdp->tx_skbuff = NULL;
 }
 
 /* format skb and descriptor buffer */
@@ -1409,43 +1458,6 @@ static void sh_eth_dev_exit(struct net_device *ndev)
 	update_mac_address(ndev);
 }
 
-/* free Tx skb function */
-static int sh_eth_txfree(struct net_device *ndev)
-{
-	struct sh_eth_private *mdp = netdev_priv(ndev);
-	struct sh_eth_txdesc *txdesc;
-	int free_num = 0;
-	int entry;
-
-	for (; mdp->cur_tx - mdp->dirty_tx > 0; mdp->dirty_tx++) {
-		entry = mdp->dirty_tx % mdp->num_tx_ring;
-		txdesc = &mdp->tx_ring[entry];
-		if (txdesc->status & cpu_to_le32(TD_TACT))
-			break;
-		/* TACT bit must be checked before all the following reads */
-		dma_rmb();
-		netif_info(mdp, tx_done, ndev,
-			   "tx entry %d status 0x%08x\n",
-			   entry, le32_to_cpu(txdesc->status));
-		/* Free the original skb. */
-		if (mdp->tx_skbuff[entry]) {
-			dma_unmap_single(&ndev->dev, le32_to_cpu(txdesc->addr),
-					 le32_to_cpu(txdesc->len) >> 16,
-					 DMA_TO_DEVICE);
-			dev_kfree_skb_irq(mdp->tx_skbuff[entry]);
-			mdp->tx_skbuff[entry] = NULL;
-			free_num++;
-		}
-		txdesc->status = cpu_to_le32(TD_TFP);
-		if (entry >= mdp->num_tx_ring - 1)
-			txdesc->status |= cpu_to_le32(TD_TDLE);
-
-		ndev->stats.tx_packets++;
-		ndev->stats.tx_bytes += le32_to_cpu(txdesc->len) >> 16;
-	}
-	return free_num;
-}
-
 /* Packet receive function */
 static int sh_eth_rx(struct net_device *ndev, u32 intr_status, int *quota)
 {
@@ -1690,7 +1702,7 @@ static void sh_eth_error(struct net_device *ndev, u32 intr_status)
 			   intr_status, mdp->cur_tx, mdp->dirty_tx,
 			   (u32)ndev->state, edtrr);
 		/* dirty buffer free */
-		sh_eth_txfree(ndev);
+		sh_eth_tx_free(ndev, true);
 
 		/* SH7712 BUG */
 		if (edtrr ^ sh_eth_get_edtrr_trns(mdp)) {
@@ -1751,7 +1763,7 @@ static irqreturn_t sh_eth_interrupt(int irq, void *netdev)
 		/* Clear Tx interrupts */
 		sh_eth_write(ndev, intr_status & cd->tx_check, EESR);
 
-		sh_eth_txfree(ndev);
+		sh_eth_tx_free(ndev, true);
 		netif_wake_queue(ndev);
 	}
 
@@ -2412,7 +2424,7 @@ static int sh_eth_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 
 	spin_lock_irqsave(&mdp->lock, flags);
 	if ((mdp->cur_tx - mdp->dirty_tx) >= (mdp->num_tx_ring - 4)) {
-		if (!sh_eth_txfree(ndev)) {
+		if (!sh_eth_tx_free(ndev, true)) {
 			netif_warn(mdp, tx_queued, ndev, "TxFD exhausted.\n");
 			netif_stop_queue(ndev);
 			spin_unlock_irqrestore(&mdp->lock, flags);
diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c
index 50d28261b6b9..b9cb697b2818 100644
--- a/drivers/net/ethernet/sfc/efx.c
+++ b/drivers/net/ethernet/sfc/efx.c
@@ -1371,6 +1371,13 @@ static unsigned int efx_wanted_parallelism(struct efx_nic *efx)
 		free_cpumask_var(thread_mask);
 	}
 
+	if (count > EFX_MAX_RX_QUEUES) {
+		netif_cond_dbg(efx, probe, efx->net_dev, !rss_cpus, warn,
+			       "Reducing number of rx queues from %u to %u.\n",
+			       count, EFX_MAX_RX_QUEUES);
+		count = EFX_MAX_RX_QUEUES;
+	}
+
 	/* If RSS is requested for the PF *and* VFs then we can't write RSS
 	 * table entries that are inaccessible to VFs
 	 */
diff --git a/drivers/net/ethernet/sfc/falcon/efx.c b/drivers/net/ethernet/sfc/falcon/efx.c
index f5e5cd1659a1..29614da91cbf 100644
--- a/drivers/net/ethernet/sfc/falcon/efx.c
+++ b/drivers/net/ethernet/sfc/falcon/efx.c
@@ -1354,6 +1354,13 @@ static unsigned int ef4_wanted_parallelism(struct ef4_nic *efx)
 		free_cpumask_var(thread_mask);
 	}
 
+	if (count > EF4_MAX_RX_QUEUES) {
+		netif_cond_dbg(efx, probe, efx->net_dev, !rss_cpus, warn,
+			       "Reducing number of rx queues from %u to %u.\n",
+			       count, EF4_MAX_RX_QUEUES);
+		count = EF4_MAX_RX_QUEUES;
+	}
+
 	return count;
 }
 
diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index b847184de6fc..2e89aab1801a 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -797,9 +797,6 @@ static struct phy_driver ksphy_driver[] = {
 	.read_status	= genphy_read_status,
 	.ack_interrupt	= kszphy_ack_interrupt,
 	.config_intr	= kszphy_config_intr,
-	.get_sset_count = kszphy_get_sset_count,
-	.get_strings	= kszphy_get_strings,
-	.get_stats	= kszphy_get_stats,
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,
 }, {
@@ -939,9 +936,6 @@ static struct phy_driver ksphy_driver[] = {
 	.read_status	= genphy_read_status,
 	.ack_interrupt	= kszphy_ack_interrupt,
 	.config_intr	= kszphy_config_intr,
-	.get_sset_count = kszphy_get_sset_count,
-	.get_strings	= kszphy_get_strings,
-	.get_stats	= kszphy_get_stats,
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,
 }, {
@@ -951,6 +945,7 @@ static struct phy_driver ksphy_driver[] = {
 	.features	= PHY_GBIT_FEATURES,
 	.flags		= PHY_HAS_MAGICANEG | PHY_HAS_INTERRUPT,
 	.driver_data	= &ksz9021_type,
+	.probe		= kszphy_probe,
 	.config_init	= ksz9021_config_init,
 	.config_aneg	= genphy_config_aneg,
 	.read_status	= genphy_read_status,
@@ -970,6 +965,7 @@ static struct phy_driver ksphy_driver[] = {
 	.features	= PHY_GBIT_FEATURES,
 	.flags		= PHY_HAS_MAGICANEG | PHY_HAS_INTERRUPT,
 	.driver_data	= &ksz9021_type,
+	.probe		= kszphy_probe,
 	.config_init	= ksz9031_config_init,
 	.config_aneg	= genphy_config_aneg,
 	.read_status	= ksz9031_read_status,
@@ -988,9 +984,6 @@ static struct phy_driver ksphy_driver[] = {
 	.config_init	= kszphy_config_init,
 	.config_aneg	= ksz8873mll_config_aneg,
 	.read_status	= ksz8873mll_read_status,
-	.get_sset_count = kszphy_get_sset_count,
-	.get_strings	= kszphy_get_strings,
-	.get_stats	= kszphy_get_stats,
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,
 }, {
@@ -1002,9 +995,6 @@ static struct phy_driver ksphy_driver[] = {
 	.config_init	= kszphy_config_init,
 	.config_aneg	= genphy_config_aneg,
 	.read_status	= genphy_read_status,
-	.get_sset_count = kszphy_get_sset_count,
-	.get_strings	= kszphy_get_strings,
-	.get_stats	= kszphy_get_stats,
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,
 }, {
@@ -1016,9 +1006,6 @@ static struct phy_driver ksphy_driver[] = {
 	.config_init	= kszphy_config_init,
 	.config_aneg	= ksz8873mll_config_aneg,
 	.read_status	= ksz8873mll_read_status,
-	.get_sset_count = kszphy_get_sset_count,
-	.get_strings	= kszphy_get_strings,
-	.get_stats	= kszphy_get_stats,
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,
 } };
diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index a84dcad2ee91..aa5d30428bba 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -1264,7 +1264,7 @@ static int vrf_fib_rule(const struct net_device *dev, __u8 family, bool add_it)
 		goto nla_put_failure;
 
 	/* rule only needs to appear once */
-	nlh->nlmsg_flags &= NLM_F_EXCL;
+	nlh->nlmsg_flags |= NLM_F_EXCL;
 
 	frh = nlmsg_data(nlh);
 	memset(frh, 0, sizeof(*frh));
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 23d4a1728cdf..351bac8f6503 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -934,8 +934,14 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
 	rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, NULL);
 	if (rc < 0)
 		goto out_unlock;
+	nvdimm_bus_unlock(&nvdimm_bus->dev);
+
 	if (copy_to_user(p, buf, buf_len))
 		rc = -EFAULT;
+
+	vfree(buf);
+	return rc;
+
  out_unlock:
 	nvdimm_bus_unlock(&nvdimm_bus->dev);
  out:
diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c
index b3323c0697f6..ca6d572c48fc 100644
--- a/drivers/nvdimm/claim.c
+++ b/drivers/nvdimm/claim.c
@@ -243,7 +243,15 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns,
 	}
 
 	if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) {
-		if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512)) {
+		/*
+		 * FIXME: nsio_rw_bytes() may be called from atomic
+		 * context in the btt case and nvdimm_clear_poison()
+		 * takes a sleeping lock. Until the locking can be
+		 * reworked this capability requires that the namespace
+		 * is not claimed by btt.
+		 */
+		if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512)
+				&& (!ndns->claim || !is_nd_btt(ndns->claim))) {
 			long cleared;
 
 			cleared = nvdimm_clear_poison(&ndns->dev, offset, size);
diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index 0eedc49e0d47..8b721321be5b 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -395,7 +395,7 @@ EXPORT_SYMBOL_GPL(nvdimm_create);
 
 int alias_dpa_busy(struct device *dev, void *data)
 {
-	resource_size_t map_end, blk_start, new, busy;
+	resource_size_t map_end, blk_start, new;
 	struct blk_alloc_info *info = data;
 	struct nd_mapping *nd_mapping;
 	struct nd_region *nd_region;
@@ -436,29 +436,19 @@ int alias_dpa_busy(struct device *dev, void *data)
  retry:
 	/*
 	 * Find the free dpa from the end of the last pmem allocation to
-	 * the end of the interleave-set mapping that is not already
-	 * covered by a blk allocation.
+	 * the end of the interleave-set mapping.
 	 */
-	busy = 0;
 	for_each_dpa_resource(ndd, res) {
+		if (strncmp(res->name, "pmem", 4) != 0)
+			continue;
 		if ((res->start >= blk_start && res->start < map_end)
 				|| (res->end >= blk_start
 					&& res->end <= map_end)) {
-			if (strncmp(res->name, "pmem", 4) == 0) {
-				new = max(blk_start, min(map_end + 1,
-							res->end + 1));
-				if (new != blk_start) {
-					blk_start = new;
-					goto retry;
-				}
-			} else
-				busy += min(map_end, res->end)
-					- max(nd_mapping->start, res->start) + 1;
-		} else if (nd_mapping->start > res->start
-				&& map_end < res->end) {
-			/* total eclipse of the PMEM region mapping */
-			busy += nd_mapping->size;
-			break;
+			new = max(blk_start, min(map_end + 1, res->end + 1));
+			if (new != blk_start) {
+				blk_start = new;
+				goto retry;
+			}
 		}
 	}
 
@@ -470,52 +460,11 @@ int alias_dpa_busy(struct device *dev, void *data)
 		return 1;
 	}
 
-	info->available -= blk_start - nd_mapping->start + busy;
+	info->available -= blk_start - nd_mapping->start;
 
 	return 0;
 }
 
-static int blk_dpa_busy(struct device *dev, void *data)
-{
-	struct blk_alloc_info *info = data;
-	struct nd_mapping *nd_mapping;
-	struct nd_region *nd_region;
-	resource_size_t map_end;
-	int i;
-
-	if (!is_nd_pmem(dev))
-		return 0;
-
-	nd_region = to_nd_region(dev);
-	for (i = 0; i < nd_region->ndr_mappings; i++) {
-		nd_mapping  = &nd_region->mapping[i];
-		if (nd_mapping->nvdimm == info->nd_mapping->nvdimm)
-			break;
-	}
-
-	if (i >= nd_region->ndr_mappings)
-		return 0;
-
-	map_end = nd_mapping->start + nd_mapping->size - 1;
-	if (info->res->start >= nd_mapping->start
-			&& info->res->start < map_end) {
-		if (info->res->end <= map_end) {
-			info->busy = 0;
-			return 1;
-		} else {
-			info->busy -= info->res->end - map_end;
-			return 0;
-		}
-	} else if (info->res->end >= nd_mapping->start
-			&& info->res->end <= map_end) {
-		info->busy -= nd_mapping->start - info->res->start;
-		return 0;
-	} else {
-		info->busy -= nd_mapping->size;
-		return 0;
-	}
-}
-
 /**
  * nd_blk_available_dpa - account the unused dpa of BLK region
  * @nd_mapping: container of dpa-resource-root + labels
@@ -545,11 +494,7 @@ resource_size_t nd_blk_available_dpa(struct nd_region *nd_region)
 	for_each_dpa_resource(ndd, res) {
 		if (strncmp(res->name, "blk", 3) != 0)
 			continue;
-
-		info.res = res;
-		info.busy = resource_size(res);
-		device_for_each_child(&nvdimm_bus->dev, &info, blk_dpa_busy);
-		info.available -= info.busy;
+		info.available -= resource_size(res);
 	}
 
 	return info.available;
diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
index 9690beb15e69..d996ca73d3be 100644
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -2023,7 +2023,7 @@ nvme_fc_configure_admin_queue(struct nvme_fc_ctrl *ctrl)
 	}
 
 	ctrl->ctrl.sqsize =
-		min_t(int, NVME_CAP_MQES(ctrl->cap) + 1, ctrl->ctrl.sqsize);
+		min_t(int, NVME_CAP_MQES(ctrl->cap), ctrl->ctrl.sqsize);
 
 	error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->cap);
 	if (error)
diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index 47a479f26e5d..16f84eb0b95e 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -1606,7 +1606,7 @@ static int nvme_rdma_configure_admin_queue(struct nvme_rdma_ctrl *ctrl)
 	}
 
 	ctrl->ctrl.sqsize =
-		min_t(int, NVME_CAP_MQES(ctrl->cap) + 1, ctrl->ctrl.sqsize);
+		min_t(int, NVME_CAP_MQES(ctrl->cap), ctrl->ctrl.sqsize);
 
 	error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->cap);
 	if (error)
diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
index 22f7bc6bac7f..c7b0b6a52708 100644
--- a/drivers/nvme/target/loop.c
+++ b/drivers/nvme/target/loop.c
@@ -392,7 +392,7 @@ static int nvme_loop_configure_admin_queue(struct nvme_loop_ctrl *ctrl)
 	}
 
 	ctrl->ctrl.sqsize =
-		min_t(int, NVME_CAP_MQES(ctrl->cap) + 1, ctrl->ctrl.sqsize);
+		min_t(int, NVME_CAP_MQES(ctrl->cap), ctrl->ctrl.sqsize);
 
 	error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->cap);
 	if (error)
diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index f1e5e65388bb..cd739d2fa160 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -275,7 +275,7 @@ int reset_control_status(struct reset_control *rstc)
 }
 EXPORT_SYMBOL_GPL(reset_control_status);
 
-static struct reset_control *__reset_control_get(
+static struct reset_control *__reset_control_get_internal(
 				struct reset_controller_dev *rcdev,
 				unsigned int index, bool shared)
 {
@@ -308,7 +308,7 @@ static struct reset_control *__reset_control_get(
 	return rstc;
 }
 
-static void __reset_control_put(struct reset_control *rstc)
+static void __reset_control_put_internal(struct reset_control *rstc)
 {
 	lockdep_assert_held(&reset_list_mutex);
 
@@ -377,7 +377,7 @@ struct reset_control *__of_reset_control_get(struct device_node *node,
 	}
 
 	/* reset_list_mutex also protects the rcdev's reset_control list */
-	rstc = __reset_control_get(rcdev, rstc_id, shared);
+	rstc = __reset_control_get_internal(rcdev, rstc_id, shared);
 
 	mutex_unlock(&reset_list_mutex);
 
@@ -385,6 +385,17 @@ struct reset_control *__of_reset_control_get(struct device_node *node,
 }
 EXPORT_SYMBOL_GPL(__of_reset_control_get);
 
+struct reset_control *__reset_control_get(struct device *dev, const char *id,
+					  int index, bool shared, bool optional)
+{
+	if (dev->of_node)
+		return __of_reset_control_get(dev->of_node, id, index, shared,
+					      optional);
+
+	return optional ? NULL : ERR_PTR(-EINVAL);
+}
+EXPORT_SYMBOL_GPL(__reset_control_get);
+
 /**
  * reset_control_put - free the reset controller
  * @rstc: reset controller
@@ -396,7 +407,7 @@ void reset_control_put(struct reset_control *rstc)
 		return;
 
 	mutex_lock(&reset_list_mutex);
-	__reset_control_put(rstc);
+	__reset_control_put_internal(rstc);
 	mutex_unlock(&reset_list_mutex);
 }
 EXPORT_SYMBOL_GPL(reset_control_put);
@@ -417,8 +428,7 @@ struct reset_control *__devm_reset_control_get(struct device *dev,
 	if (!ptr)
 		return ERR_PTR(-ENOMEM);
 
-	rstc = __of_reset_control_get(dev ? dev->of_node : NULL,
-				      id, index, shared, optional);
+	rstc = __reset_control_get(dev, id, index, shared, optional);
 	if (!IS_ERR(rstc)) {
 		*ptr = rstc;
 		devres_add(dev, ptr);
diff --git a/drivers/scsi/aacraid/aacraid.h b/drivers/scsi/aacraid/aacraid.h
index d036a806f31c..d281492009fb 100644
--- a/drivers/scsi/aacraid/aacraid.h
+++ b/drivers/scsi/aacraid/aacraid.h
@@ -1690,9 +1690,6 @@ struct aac_dev
 #define aac_adapter_sync_cmd(dev, command, p1, p2, p3, p4, p5, p6, status, r1, r2, r3, r4) \
 	(dev)->a_ops.adapter_sync_cmd(dev, command, p1, p2, p3, p4, p5, p6, status, r1, r2, r3, r4)
 
-#define aac_adapter_check_health(dev) \
-	(dev)->a_ops.adapter_check_health(dev)
-
 #define aac_adapter_restart(dev, bled, reset_type) \
 	((dev)->a_ops.adapter_restart(dev, bled, reset_type))
 
@@ -2615,6 +2612,14 @@ static inline unsigned int cap_to_cyls(sector_t capacity, unsigned divisor)
 	return capacity;
 }
 
+static inline int aac_adapter_check_health(struct aac_dev *dev)
+{
+	if (unlikely(pci_channel_offline(dev->pdev)))
+		return -1;
+
+	return (dev)->a_ops.adapter_check_health(dev);
+}
+
 /* SCp.phase values */
 #define AAC_OWNER_MIDLEVEL	0x101
 #define AAC_OWNER_LOWLEVEL	0x102
diff --git a/drivers/scsi/aacraid/commsup.c b/drivers/scsi/aacraid/commsup.c
index c8172f16cf33..1f4918355fdb 100644
--- a/drivers/scsi/aacraid/commsup.c
+++ b/drivers/scsi/aacraid/commsup.c
@@ -1873,7 +1873,8 @@ int aac_check_health(struct aac_dev * aac)
 	spin_unlock_irqrestore(&aac->fib_lock, flagv);
 
 	if (BlinkLED < 0) {
-		printk(KERN_ERR "%s: Host adapter dead %d\n", aac->name, BlinkLED);
+		printk(KERN_ERR "%s: Host adapter is dead (or got a PCI error) %d\n",
+				aac->name, BlinkLED);
 		goto out;
 	}
 
diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index b29afafc2885..5d5e272fd815 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -6293,7 +6293,12 @@ static void ipr_erp_start(struct ipr_ioa_cfg *ioa_cfg,
 		break;
 	case IPR_IOASC_MED_DO_NOT_REALLOC: /* prevent retries */
 	case IPR_IOASA_IR_DUAL_IOA_DISABLED:
-		scsi_cmd->result |= (DID_PASSTHROUGH << 16);
+		/*
+		 * exception: do not set DID_PASSTHROUGH on CHECK CONDITION
+		 * so SCSI mid-layer and upper layers handle it accordingly.
+		 */
+		if (scsi_cmd->result != SAM_STAT_CHECK_CONDITION)
+			scsi_cmd->result |= (DID_PASSTHROUGH << 16);
 		break;
 	case IPR_IOASC_BUS_WAS_RESET:
 	case IPR_IOASC_BUS_WAS_RESET_BY_OTHER:
diff --git a/drivers/scsi/qedf/qedf_fip.c b/drivers/scsi/qedf/qedf_fip.c
index ed58b9104f58..e10b91cc3c62 100644
--- a/drivers/scsi/qedf/qedf_fip.c
+++ b/drivers/scsi/qedf/qedf_fip.c
@@ -99,7 +99,8 @@ static void qedf_fcoe_process_vlan_resp(struct qedf_ctx *qedf,
 		qedf_set_vlan_id(qedf, vid);
 
 		/* Inform waiter that it's ok to call fcoe_ctlr_link up() */
-		complete(&qedf->fipvlan_compl);
+		if (!completion_done(&qedf->fipvlan_compl))
+			complete(&qedf->fipvlan_compl);
 	}
 }
 
diff --git a/drivers/scsi/qedf/qedf_main.c b/drivers/scsi/qedf/qedf_main.c
index 8e2a160490e6..cceddd995a4b 100644
--- a/drivers/scsi/qedf/qedf_main.c
+++ b/drivers/scsi/qedf/qedf_main.c
@@ -2803,6 +2803,7 @@ static int __qedf_probe(struct pci_dev *pdev, int mode)
 		atomic_set(&qedf->num_offloads, 0);
 		qedf->stop_io_on_error = false;
 		pci_set_drvdata(pdev, qedf);
+		init_completion(&qedf->fipvlan_compl);
 
 		QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_INFO,
 		   "QLogic FastLinQ FCoE Module qedf %s, "
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 3e7011757c82..83d61d2142e9 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -1160,8 +1160,13 @@ static inline
 uint32_t qla2x00_isp_reg_stat(struct qla_hw_data *ha)
 {
 	struct device_reg_24xx __iomem *reg = &ha->iobase->isp24;
+	struct device_reg_82xx __iomem *reg82 = &ha->iobase->isp82;
 
-	return ((RD_REG_DWORD(&reg->host_status)) == ISP_REG_DISCONNECT);
+	if (IS_P3P_TYPE(ha))
+		return ((RD_REG_DWORD(&reg82->host_int)) == ISP_REG_DISCONNECT);
+	else
+		return ((RD_REG_DWORD(&reg->host_status)) ==
+			ISP_REG_DISCONNECT);
 }
 
 /**************************************************************************
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index fcfeddc79331..35ad5e8a31ab 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -2102,6 +2102,22 @@ static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
 
 #define READ_CAPACITY_RETRIES_ON_RESET	10
 
+/*
+ * Ensure that we don't overflow sector_t when CONFIG_LBDAF is not set
+ * and the reported logical block size is bigger than 512 bytes. Note
+ * that last_sector is a u64 and therefore logical_to_sectors() is not
+ * applicable.
+ */
+static bool sd_addressable_capacity(u64 lba, unsigned int sector_size)
+{
+	u64 last_sector = (lba + 1ULL) << (ilog2(sector_size) - 9);
+
+	if (sizeof(sector_t) == 4 && last_sector > U32_MAX)
+		return false;
+
+	return true;
+}
+
 static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
 						unsigned char *buffer)
 {
@@ -2167,7 +2183,7 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
 		return -ENODEV;
 	}
 
-	if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) {
+	if (!sd_addressable_capacity(lba, sector_size)) {
 		sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
 			"kernel compiled with support for large block "
 			"devices.\n");
@@ -2256,7 +2272,7 @@ static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
 		return sector_size;
 	}
 
-	if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
+	if (!sd_addressable_capacity(lba, sector_size)) {
 		sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
 			"kernel compiled with support for large block "
 			"devices.\n");
@@ -2956,7 +2972,8 @@ static int sd_revalidate_disk(struct gendisk *disk)
 		q->limits.io_opt = logical_to_bytes(sdp, sdkp->opt_xfer_blocks);
 		rw_max = logical_to_sectors(sdp, sdkp->opt_xfer_blocks);
 	} else
-		rw_max = BLK_DEF_MAX_SECTORS;
+		rw_max = min_not_zero(logical_to_sectors(sdp, dev_max),
+				      (sector_t)BLK_DEF_MAX_SECTORS);
 
 	/* Combine with controller limits */
 	q->limits.max_sectors = min(rw_max, queue_max_hw_sectors(q));
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 0b29b9329b1c..a8f630213a1a 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -836,6 +836,7 @@ static void get_capabilities(struct scsi_cd *cd)
 	unsigned char *buffer;
 	struct scsi_mode_data data;
 	struct scsi_sense_hdr sshdr;
+	unsigned int ms_len = 128;
 	int rc, n;
 
 	static const char *loadmech[] =
@@ -862,10 +863,11 @@ static void get_capabilities(struct scsi_cd *cd)
 	scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
 
 	/* ask for mode page 0x2a */
-	rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, 128,
+	rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, ms_len,
 			     SR_TIMEOUT, 3, &data, NULL);
 
-	if (!scsi_status_is_good(rc)) {
+	if (!scsi_status_is_good(rc) || data.length > ms_len ||
+	    data.header_length + data.block_descriptor_length > data.length) {
 		/* failed, drive doesn't have capabilities mode page */
 		cd->cdi.speed = 1;
 		cd->cdi.mask |= (CDC_CD_R | CDC_CD_RW | CDC_DVD_R |
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index b0500a0a87b8..e4603b09863a 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -492,6 +492,41 @@ static void tty_ldisc_close(struct tty_struct *tty, struct tty_ldisc *ld)
 }
 
 /**
+ *	tty_ldisc_restore	-	helper for tty ldisc change
+ *	@tty: tty to recover
+ *	@old: previous ldisc
+ *
+ *	Restore the previous line discipline or N_TTY when a line discipline
+ *	change fails due to an open error
+ */
+
+static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old)
+{
+	struct tty_ldisc *new_ldisc;
+	int r;
+
+	/* There is an outstanding reference here so this is safe */
+	old = tty_ldisc_get(tty, old->ops->num);
+	WARN_ON(IS_ERR(old));
+	tty->ldisc = old;
+	tty_set_termios_ldisc(tty, old->ops->num);
+	if (tty_ldisc_open(tty, old) < 0) {
+		tty_ldisc_put(old);
+		/* This driver is always present */
+		new_ldisc = tty_ldisc_get(tty, N_TTY);
+		if (IS_ERR(new_ldisc))
+			panic("n_tty: get");
+		tty->ldisc = new_ldisc;
+		tty_set_termios_ldisc(tty, N_TTY);
+		r = tty_ldisc_open(tty, new_ldisc);
+		if (r < 0)
+			panic("Couldn't open N_TTY ldisc for "
+			      "%s --- error %d.",
+			      tty_name(tty), r);
+	}
+}
+
+/**
  *	tty_set_ldisc		-	set line discipline
  *	@tty: the terminal to set
  *	@ldisc: the line discipline
@@ -504,7 +539,12 @@ static void tty_ldisc_close(struct tty_struct *tty, struct tty_ldisc *ld)
 
 int tty_set_ldisc(struct tty_struct *tty, int disc)
 {
-	int retval, old_disc;
+	int retval;
+	struct tty_ldisc *old_ldisc, *new_ldisc;
+
+	new_ldisc = tty_ldisc_get(tty, disc);
+	if (IS_ERR(new_ldisc))
+		return PTR_ERR(new_ldisc);
 
 	tty_lock(tty);
 	retval = tty_ldisc_lock(tty, 5 * HZ);
@@ -517,8 +557,7 @@ int tty_set_ldisc(struct tty_struct *tty, int disc)
 	}
 
 	/* Check the no-op case */
-	old_disc = tty->ldisc->ops->num;
-	if (old_disc == disc)
+	if (tty->ldisc->ops->num == disc)
 		goto out;
 
 	if (test_bit(TTY_HUPPED, &tty->flags)) {
@@ -527,25 +566,34 @@ int tty_set_ldisc(struct tty_struct *tty, int disc)
 		goto out;
 	}
 
-	retval = tty_ldisc_reinit(tty, disc);
+	old_ldisc = tty->ldisc;
+
+	/* Shutdown the old discipline. */
+	tty_ldisc_close(tty, old_ldisc);
+
+	/* Now set up the new line discipline. */
+	tty->ldisc = new_ldisc;
+	tty_set_termios_ldisc(tty, disc);
+
+	retval = tty_ldisc_open(tty, new_ldisc);
 	if (retval < 0) {
 		/* Back to the old one or N_TTY if we can't */
-		if (tty_ldisc_reinit(tty, old_disc) < 0) {
-			pr_err("tty: TIOCSETD failed, reinitializing N_TTY\n");
-			if (tty_ldisc_reinit(tty, N_TTY) < 0) {
-				/* At this point we have tty->ldisc == NULL. */
-				pr_err("tty: reinitializing N_TTY failed\n");
-			}
-		}
+		tty_ldisc_put(new_ldisc);
+		tty_ldisc_restore(tty, old_ldisc);
 	}
 
-	if (tty->ldisc && tty->ldisc->ops->num != old_disc &&
-	    tty->ops->set_ldisc) {
+	if (tty->ldisc->ops->num != old_ldisc->ops->num && tty->ops->set_ldisc) {
 		down_read(&tty->termios_rwsem);
 		tty->ops->set_ldisc(tty);
 		up_read(&tty->termios_rwsem);
 	}
 
+	/* At this point we hold a reference to the new ldisc and a
+	   reference to the old ldisc, or we hold two references to
+	   the old ldisc (if it was restored as part of error cleanup
+	   above). In either case, releasing a single reference from
+	   the old ldisc is correct. */
+	new_ldisc = old_ldisc;
 out:
 	tty_ldisc_unlock(tty);
 
@@ -553,6 +601,7 @@ out:
 	   already running */
 	tty_buffer_restart_work(tty->port);
 err:
+	tty_ldisc_put(new_ldisc);	/* drop the extra reference */
 	tty_unlock(tty);
 	return retval;
 }
@@ -613,8 +662,10 @@ int tty_ldisc_reinit(struct tty_struct *tty, int disc)
 	int retval;
 
 	ld = tty_ldisc_get(tty, disc);
-	if (IS_ERR(ld))
+	if (IS_ERR(ld)) {
+		BUG_ON(disc == N_TTY);
 		return PTR_ERR(ld);
+	}
 
 	if (tty->ldisc) {
 		tty_ldisc_close(tty, tty->ldisc);
@@ -626,8 +677,10 @@ int tty_ldisc_reinit(struct tty_struct *tty, int disc)
 	tty_set_termios_ldisc(tty, disc);
 	retval = tty_ldisc_open(tty, tty->ldisc);
 	if (retval) {
-		tty_ldisc_put(tty->ldisc);
-		tty->ldisc = NULL;
+		if (!WARN_ON(disc == N_TTY)) {
+			tty_ldisc_put(tty->ldisc);
+			tty->ldisc = NULL;
+		}
 	}
 	return retval;
 }