diff --git a/MAINTAINERS b/MAINTAINERS
index 9777a1dd6ff647..4c05e18ced505d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5930,7 +5930,7 @@ F:	Documentation/dev-tools/gcov.rst
 
 GDB KERNEL DEBUGGING HELPER SCRIPTS
 M:	Jan Kiszka <jan.kiszka@siemens.com>
-M:	Kieran Bingham <kieran@bingham.xyz>
+M:	Kieran Bingham <kbingham@kernel.org>
 S:	Supported
 F:	scripts/gdb/
 
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 46f656b8fc233a..e7705dde953fc7 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -11,7 +11,6 @@ config PARISC
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_STRICT_KERNEL_RWX
 	select ARCH_HAS_UBSAN_SANITIZE_ALL
-	select ARCH_WANTS_UBSAN_NO_NULL
 	select ARCH_SUPPORTS_MEMORY_FAILURE
 	select RTC_CLASS
 	select RTC_DRV_GENERIC
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 8a1863d9ed5338..4fe5b2affa2330 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -106,7 +106,6 @@ config S390
 	select ARCH_USE_BUILTIN_BSWAP
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
-	select ARCH_WANTS_UBSAN_NO_NULL
 	select ARCH_WANT_IPC_PARSE_VERSION
 	select BUILDTIME_EXTABLE_SORT
 	select CLONE_BACKWARDS2
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 7436b2d27fa385..a390c6d4f72df9 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -298,7 +298,8 @@ static void reset_bdev(struct zram *zram)
 	zram->backing_dev = NULL;
 	zram->old_block_size = 0;
 	zram->bdev = NULL;
-
+	zram->disk->queue->backing_dev_info->capabilities |=
+				BDI_CAP_SYNCHRONOUS_IO;
 	kvfree(zram->bitmap);
 	zram->bitmap = NULL;
 }
@@ -400,6 +401,18 @@ static ssize_t backing_dev_store(struct device *dev,
 	zram->backing_dev = backing_dev;
 	zram->bitmap = bitmap;
 	zram->nr_pages = nr_pages;
+	/*
+	 * With writeback feature, zram does asynchronous IO so it's no longer
+	 * synchronous device so let's remove synchronous io flag. Othewise,
+	 * upper layer(e.g., swap) could wait IO completion rather than
+	 * (submit and return), which will cause system sluggish.
+	 * Furthermore, when the IO function returns(e.g., swap_readpage),
+	 * upper layer expects IO was done so it could deallocate the page
+	 * freely but in fact, IO is going on so finally could cause
+	 * use-after-free when the IO is really done.
+	 */
+	zram->disk->queue->backing_dev_info->capabilities &=
+			~BDI_CAP_SYNCHRONOUS_IO;
 	up_write(&zram->init_lock);
 
 	pr_info("setup backing device %s\n", file_name);
diff --git a/drivers/i2c/busses/i2c-xlp9xx.c b/drivers/i2c/busses/i2c-xlp9xx.c
index 1f41a4f89c08f4..8a873975cf1252 100644
--- a/drivers/i2c/busses/i2c-xlp9xx.c
+++ b/drivers/i2c/busses/i2c-xlp9xx.c
@@ -191,28 +191,43 @@ static void xlp9xx_i2c_drain_rx_fifo(struct xlp9xx_i2c_dev *priv)
 	if (priv->len_recv) {
 		/* read length byte */
 		rlen = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_MRXFIFO);
+
+		/*
+		 * We expect at least 2 interrupts for I2C_M_RECV_LEN
+		 * transactions. The length is updated during the first
+		 * interrupt, and the buffer contents are only copied
+		 * during subsequent interrupts. If in case the interrupts
+		 * get merged we would complete the transaction without
+		 * copying out the bytes from RX fifo. To avoid this now we
+		 * drain the fifo as and when data is available.
+		 * We drained the rlen byte already, decrement total length
+		 * by one.
+		 */
+
+		len--;
 		if (rlen > I2C_SMBUS_BLOCK_MAX || rlen == 0) {
 			rlen = 0;	/*abort transfer */
 			priv->msg_buf_remaining = 0;
 			priv->msg_len = 0;
-		} else {
-			*buf++ = rlen;
-			if (priv->client_pec)
-				++rlen; /* account for error check byte */
-			/* update remaining bytes and message length */
-			priv->msg_buf_remaining = rlen;
-			priv->msg_len = rlen + 1;
+			xlp9xx_i2c_update_rlen(priv);
+			return;
 		}
+
+		*buf++ = rlen;
+		if (priv->client_pec)
+			++rlen; /* account for error check byte */
+		/* update remaining bytes and message length */
+		priv->msg_buf_remaining = rlen;
+		priv->msg_len = rlen + 1;
 		xlp9xx_i2c_update_rlen(priv);
 		priv->len_recv = false;
-	} else {
-		len = min(priv->msg_buf_remaining, len);
-		for (i = 0; i < len; i++, buf++)
-			*buf = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_MRXFIFO);
-
-		priv->msg_buf_remaining -= len;
 	}
 
+	len = min(priv->msg_buf_remaining, len);
+	for (i = 0; i < len; i++, buf++)
+		*buf = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_MRXFIFO);
+
+	priv->msg_buf_remaining -= len;
 	priv->msg_buf = buf;
 
 	if (priv->msg_buf_remaining)
diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index f051ce35a440aa..832bce07c38519 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -2358,14 +2358,16 @@ static int cpsw_ndo_vlan_rx_add_vid(struct net_device *ndev,
 		int i;
 
 		for (i = 0; i < cpsw->data.slaves; i++) {
-			if (vid == cpsw->slaves[i].port_vlan)
-				return -EINVAL;
+			if (vid == cpsw->slaves[i].port_vlan) {
+				ret = -EINVAL;
+				goto err;
+			}
 		}
 	}
 
 	dev_info(priv->dev, "Adding vlanid %d to vlan filter\n", vid);
 	ret = cpsw_add_vlan_ale_entry(priv, vid);
-
+err:
 	pm_runtime_put(cpsw->dev);
 	return ret;
 }
@@ -2391,22 +2393,17 @@ static int cpsw_ndo_vlan_rx_kill_vid(struct net_device *ndev,
 
 		for (i = 0; i < cpsw->data.slaves; i++) {
 			if (vid == cpsw->slaves[i].port_vlan)
-				return -EINVAL;
+				goto err;
 		}
 	}
 
 	dev_info(priv->dev, "removing vlanid %d from vlan filter\n", vid);
 	ret = cpsw_ale_del_vlan(cpsw->ale, vid, 0);
-	if (ret != 0)
-		return ret;
-
-	ret = cpsw_ale_del_ucast(cpsw->ale, priv->mac_addr,
-				 HOST_PORT_NUM, ALE_VLAN, vid);
-	if (ret != 0)
-		return ret;
-
-	ret = cpsw_ale_del_mcast(cpsw->ale, priv->ndev->broadcast,
-				 0, ALE_VLAN, vid);
+	ret |= cpsw_ale_del_ucast(cpsw->ale, priv->mac_addr,
+				  HOST_PORT_NUM, ALE_VLAN, vid);
+	ret |= cpsw_ale_del_mcast(cpsw->ale, priv->ndev->broadcast,
+				  0, ALE_VLAN, vid);
+err:
 	pm_runtime_put(cpsw->dev);
 	return ret;
 }
diff --git a/drivers/net/ethernet/ti/cpsw_ale.c b/drivers/net/ethernet/ti/cpsw_ale.c
index 93dc05c194d381..5766225a4ce117 100644
--- a/drivers/net/ethernet/ti/cpsw_ale.c
+++ b/drivers/net/ethernet/ti/cpsw_ale.c
@@ -394,7 +394,7 @@ int cpsw_ale_del_mcast(struct cpsw_ale *ale, u8 *addr, int port_mask,
 
 	idx = cpsw_ale_match_addr(ale, addr, (flags & ALE_VLAN) ? vid : 0);
 	if (idx < 0)
-		return -EINVAL;
+		return -ENOENT;
 
 	cpsw_ale_read(ale, idx, ale_entry);
 
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 799cba4624a5e0..2ff874b6ec89ab 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -895,7 +895,6 @@ static RING_IDX xennet_fill_frags(struct netfront_queue *queue,
 				  struct sk_buff *skb,
 				  struct sk_buff_head *list)
 {
-	struct skb_shared_info *shinfo = skb_shinfo(skb);
 	RING_IDX cons = queue->rx.rsp_cons;
 	struct sk_buff *nskb;
 
@@ -904,15 +903,16 @@ static RING_IDX xennet_fill_frags(struct netfront_queue *queue,
 			RING_GET_RESPONSE(&queue->rx, ++cons);
 		skb_frag_t *nfrag = &skb_shinfo(nskb)->frags[0];
 
-		if (shinfo->nr_frags == MAX_SKB_FRAGS) {
+		if (skb_shinfo(skb)->nr_frags == MAX_SKB_FRAGS) {
 			unsigned int pull_to = NETFRONT_SKB_CB(skb)->pull_to;
 
 			BUG_ON(pull_to <= skb_headlen(skb));
 			__pskb_pull_tail(skb, pull_to - skb_headlen(skb));
 		}
-		BUG_ON(shinfo->nr_frags >= MAX_SKB_FRAGS);
+		BUG_ON(skb_shinfo(skb)->nr_frags >= MAX_SKB_FRAGS);
 
-		skb_add_rx_frag(skb, shinfo->nr_frags, skb_frag_page(nfrag),
+		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
+				skb_frag_page(nfrag),
 				rx->offset, rx->status, PAGE_SIZE);
 
 		skb_shinfo(nskb)->nr_frags = 0;
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index e0918d180f08e6..46f5f29605d474 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -69,7 +69,7 @@ struct bpf_cpu_map {
 };
 
 static int bq_flush_to_queue(struct bpf_cpu_map_entry *rcpu,
-			     struct xdp_bulk_queue *bq);
+			     struct xdp_bulk_queue *bq, bool in_napi_ctx);
 
 static u64 cpu_map_bitmap_size(const union bpf_attr *attr)
 {
@@ -375,7 +375,7 @@ static void __cpu_map_entry_free(struct rcu_head *rcu)
 		struct xdp_bulk_queue *bq = per_cpu_ptr(rcpu->bulkq, cpu);
 
 		/* No concurrent bq_enqueue can run at this point */
-		bq_flush_to_queue(rcpu, bq);
+		bq_flush_to_queue(rcpu, bq, false);
 	}
 	free_percpu(rcpu->bulkq);
 	/* Cannot kthread_stop() here, last put free rcpu resources */
@@ -558,7 +558,7 @@ const struct bpf_map_ops cpu_map_ops = {
 };
 
 static int bq_flush_to_queue(struct bpf_cpu_map_entry *rcpu,
-			     struct xdp_bulk_queue *bq)
+			     struct xdp_bulk_queue *bq, bool in_napi_ctx)
 {
 	unsigned int processed = 0, drops = 0;
 	const int to_cpu = rcpu->cpu;
@@ -578,7 +578,10 @@ static int bq_flush_to_queue(struct bpf_cpu_map_entry *rcpu,
 		err = __ptr_ring_produce(q, xdpf);
 		if (err) {
 			drops++;
-			xdp_return_frame_rx_napi(xdpf);
+			if (likely(in_napi_ctx))
+				xdp_return_frame_rx_napi(xdpf);
+			else
+				xdp_return_frame(xdpf);
 		}
 		processed++;
 	}
@@ -598,7 +601,7 @@ static int bq_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_frame *xdpf)
 	struct xdp_bulk_queue *bq = this_cpu_ptr(rcpu->bulkq);
 
 	if (unlikely(bq->count == CPU_MAP_BULK_SIZE))
-		bq_flush_to_queue(rcpu, bq);
+		bq_flush_to_queue(rcpu, bq, true);
 
 	/* Notice, xdp_buff/page MUST be queued here, long enough for
 	 * driver to code invoking us to finished, due to driver
@@ -661,7 +664,7 @@ void __cpu_map_flush(struct bpf_map *map)
 
 		/* Flush all frames in bulkq to real queue */
 		bq = this_cpu_ptr(rcpu->bulkq);
-		bq_flush_to_queue(rcpu, bq);
+		bq_flush_to_queue(rcpu, bq, true);
 
 		/* If already running, costs spin_lock_irqsave + smb_mb */
 		wake_up_process(rcpu->kthread);
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index d361fc1e3bf35f..750d45edae7989 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -217,7 +217,8 @@ void __dev_map_insert_ctx(struct bpf_map *map, u32 bit)
 }
 
 static int bq_xmit_all(struct bpf_dtab_netdev *obj,
-		       struct xdp_bulk_queue *bq, u32 flags)
+		       struct xdp_bulk_queue *bq, u32 flags,
+		       bool in_napi_ctx)
 {
 	struct net_device *dev = obj->dev;
 	int sent = 0, drops = 0, err = 0;
@@ -254,7 +255,10 @@ static int bq_xmit_all(struct bpf_dtab_netdev *obj,
 		struct xdp_frame *xdpf = bq->q[i];
 
 		/* RX path under NAPI protection, can return frames faster */
-		xdp_return_frame_rx_napi(xdpf);
+		if (likely(in_napi_ctx))
+			xdp_return_frame_rx_napi(xdpf);
+		else
+			xdp_return_frame(xdpf);
 		drops++;
 	}
 	goto out;
@@ -286,7 +290,7 @@ void __dev_map_flush(struct bpf_map *map)
 		__clear_bit(bit, bitmap);
 
 		bq = this_cpu_ptr(dev->bulkq);
-		bq_xmit_all(dev, bq, XDP_XMIT_FLUSH);
+		bq_xmit_all(dev, bq, XDP_XMIT_FLUSH, true);
 	}
 }
 
@@ -316,7 +320,7 @@ static int bq_enqueue(struct bpf_dtab_netdev *obj, struct xdp_frame *xdpf,
 	struct xdp_bulk_queue *bq = this_cpu_ptr(obj->bulkq);
 
 	if (unlikely(bq->count == DEV_MAP_BULK_SIZE))
-		bq_xmit_all(obj, bq, 0);
+		bq_xmit_all(obj, bq, 0, true);
 
 	/* Ingress dev_rx will be the same for all xdp_frame's in
 	 * bulk_queue, because bq stored per-CPU and must be flushed
@@ -385,7 +389,7 @@ static void dev_map_flush_old(struct bpf_dtab_netdev *dev)
 			__clear_bit(dev->bit, bitmap);
 
 			bq = per_cpu_ptr(dev->bulkq, cpu);
-			bq_xmit_all(dev, bq, XDP_XMIT_FLUSH);
+			bq_xmit_all(dev, bq, XDP_XMIT_FLUSH, false);
 		}
 	}
 }
diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c
index 0b38be5a955c25..70c0755e8fc4e1 100644
--- a/kernel/bpf/sockmap.c
+++ b/kernel/bpf/sockmap.c
@@ -1045,12 +1045,12 @@ static int bpf_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
 
 	while (msg_data_left(msg)) {
-		struct sk_msg_buff *m;
+		struct sk_msg_buff *m = NULL;
 		bool enospc = false;
 		int copy;
 
 		if (sk->sk_err) {
-			err = sk->sk_err;
+			err = -sk->sk_err;
 			goto out_err;
 		}
 
@@ -1113,8 +1113,11 @@ static int bpf_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
 wait_for_memory:
 		err = sk_stream_wait_memory(sk, &timeo);
-		if (err)
+		if (err) {
+			if (m && m != psock->cork)
+				free_start_sg(sk, m);
 			goto out_err;
+		}
 	}
 out_err:
 	if (err < 0)
diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan
index 19d42ea75ec225..98fa559ebd8086 100644
--- a/lib/Kconfig.ubsan
+++ b/lib/Kconfig.ubsan
@@ -1,9 +1,6 @@
 config ARCH_HAS_UBSAN_SANITIZE_ALL
 	bool
 
-config ARCH_WANTS_UBSAN_NO_NULL
-	def_bool n
-
 config UBSAN
 	bool "Undefined behaviour sanity checker"
 	help
@@ -39,14 +36,6 @@ config UBSAN_ALIGNMENT
 	  Enabling this option on architectures that support unaligned
 	  accesses may produce a lot of false positives.
 
-config UBSAN_NULL
-	bool "Enable checking of null pointers"
-	depends on UBSAN
-	default y if !ARCH_WANTS_UBSAN_NO_NULL
-	help
-	  This option enables detection of memory accesses via a
-	  null pointer.
-
 config TEST_UBSAN
 	tristate "Module for testing for undefined behavior detection"
 	depends on m && UBSAN
diff --git a/mm/memory.c b/mm/memory.c
index dab1511294add1..c5e87a3a82ba34 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4395,6 +4395,9 @@ int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
 		return -EINVAL;
 
 	maddr = ioremap_prot(phys_addr, PAGE_ALIGN(len + offset), prot);
+	if (!maddr)
+		return -ENOMEM;
+
 	if (write)
 		memcpy_toio(maddr + offset, buf, len);
 	else
diff --git a/samples/bpf/xdp_redirect_cpu_kern.c b/samples/bpf/xdp_redirect_cpu_kern.c
index 8cb703671b0468..0cc3d71057f03d 100644
--- a/samples/bpf/xdp_redirect_cpu_kern.c
+++ b/samples/bpf/xdp_redirect_cpu_kern.c
@@ -14,7 +14,7 @@
 #include <uapi/linux/bpf.h>
 #include "bpf_helpers.h"
 
-#define MAX_CPUS 12 /* WARNING - sync with _user.c */
+#define MAX_CPUS 64 /* WARNING - sync with _user.c */
 
 /* Special map type that can XDP_REDIRECT frames to another CPU */
 struct bpf_map_def SEC("maps") cpu_map = {
diff --git a/samples/bpf/xdp_redirect_cpu_user.c b/samples/bpf/xdp_redirect_cpu_user.c
index f6efaefd485b15..4b4d78fffe3042 100644
--- a/samples/bpf/xdp_redirect_cpu_user.c
+++ b/samples/bpf/xdp_redirect_cpu_user.c
@@ -19,7 +19,7 @@ static const char *__doc__ =
 #include <arpa/inet.h>
 #include <linux/if_link.h>
 
-#define MAX_CPUS 12 /* WARNING - sync with _kern.c */
+#define MAX_CPUS 64 /* WARNING - sync with _kern.c */
 
 /* How many xdp_progs are defined in _kern.c */
 #define MAX_PROG 5
@@ -527,7 +527,7 @@ static void stress_cpumap(void)
 	 * procedure.
 	 */
 	create_cpu_entry(1,  1024, 0, false);
-	create_cpu_entry(1,   128, 0, false);
+	create_cpu_entry(1,     8, 0, false);
 	create_cpu_entry(1, 16000, 0, false);
 }
 
diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan
index b593b36ccff869..38b2b4818e8ebf 100644
--- a/scripts/Makefile.ubsan
+++ b/scripts/Makefile.ubsan
@@ -14,10 +14,6 @@ ifdef CONFIG_UBSAN_ALIGNMENT
       CFLAGS_UBSAN += $(call cc-option, -fsanitize=alignment)
 endif
 
-ifdef CONFIG_UBSAN_NULL
-      CFLAGS_UBSAN += $(call cc-option, -fsanitize=null)
-endif
-
       # -fsanitize=* options makes GCC less smart than usual and
       # increase number of 'maybe-uninitialized false-positives
       CFLAGS_UBSAN += $(call cc-option, -Wno-maybe-uninitialized)
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 09ecf8162f7a8a..cf94b0770522ff 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+// SPDX-License-Identifier: LGPL-2.1
 /* Copyright (c) 2018 Facebook */
 
 #include <stdlib.h>
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index 43c658ccfc2ba4..4897e0724d4ec6 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+/* SPDX-License-Identifier: LGPL-2.1 */
 /* Copyright (c) 2018 Facebook */
 
 #ifndef __BPF_BTF_H
diff --git a/tools/testing/selftests/bpf/test_sockmap.c b/tools/testing/selftests/bpf/test_sockmap.c
index 9e78df20791936..0c7d9e556b47d0 100644
--- a/tools/testing/selftests/bpf/test_sockmap.c
+++ b/tools/testing/selftests/bpf/test_sockmap.c
@@ -354,7 +354,7 @@ static int msg_loop(int fd, int iov_count, int iov_length, int cnt,
 		while (s->bytes_recvd < total_bytes) {
 			if (txmsg_cork) {
 				timeout.tv_sec = 0;
-				timeout.tv_usec = 1000;
+				timeout.tv_usec = 300000;
 			} else {
 				timeout.tv_sec = 1;
 				timeout.tv_usec = 0;