diff --git a/Makefile b/Makefile
index ac2a241..32d26d0 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 VERSION = 3
 PATCHLEVEL = 0
-SUBLEVEL = 84
-EXTRAVERSION =
+SUBLEVEL = 85
+EXTRAVERSION = -rc1
 NAME = Sneaky Weasel
 
 # *DOCUMENTATION*
diff --git a/drivers/net/wan/dlci.c b/drivers/net/wan/dlci.c
index 21b104d..af44b93 100644
--- a/drivers/net/wan/dlci.c
+++ b/drivers/net/wan/dlci.c
@@ -377,21 +377,37 @@ static int dlci_del(struct dlci_add *dlci)
 	struct frad_local	*flp;
 	struct net_device	*master, *slave;
 	int			err;
+	bool			found = false;
+
+	rtnl_lock();
 
 	/* validate slave device */
 	master = __dev_get_by_name(&init_net, dlci->devname);
-	if (!master)
-		return -ENODEV;
+	if (!master) {
+		err = -ENODEV;
+		goto out;
+	}
+
+	list_for_each_entry(dlp, &dlci_devs, list) {
+		if (dlp->master == master) {
+			found = true;
+			break;
+		}
+	}
+	if (!found) {
+		err = -ENODEV;
+		goto out;
+	}
 
 	if (netif_running(master)) {
-		return -EBUSY;
+		err = -EBUSY;
+		goto out;
 	}
 
 	dlp = netdev_priv(master);
 	slave = dlp->slave;
 	flp = netdev_priv(slave);
 
-	rtnl_lock();
 	err = (*flp->deassoc)(slave, master);
 	if (!err) {
 		list_del(&dlp->list);
@@ -400,8 +416,8 @@ static int dlci_del(struct dlci_add *dlci)
 
 		dev_put(slave);
 	}
+out:
 	rtnl_unlock();
-
 	return err;
 }
 
diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index 73038ba..78c26ca 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -935,22 +935,37 @@ static unsigned int dma_handle_tx(struct eg20t_port *priv)
 static void pch_uart_err_ir(struct eg20t_port *priv, unsigned int lsr)
 {
 	u8 fcr = ioread8(priv->membase + UART_FCR);
+	struct uart_port *port = &priv->port;
+	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
+	char   *error_msg[5] = {};
+	int    i = 0;
 
 	/* Reset FIFO */
 	fcr |= UART_FCR_CLEAR_RCVR;
 	iowrite8(fcr, priv->membase + UART_FCR);
 
 	if (lsr & PCH_UART_LSR_ERR)
-		dev_err(&priv->pdev->dev, "Error data in FIFO\n");
+		error_msg[i++] = "Error data in FIFO\n";
 
-	if (lsr & UART_LSR_FE)
-		dev_err(&priv->pdev->dev, "Framing Error\n");
+	if (lsr & UART_LSR_FE) {
+		port->icount.frame++;
+		error_msg[i++] = "  Framing Error\n";
+	}
 
-	if (lsr & UART_LSR_PE)
-		dev_err(&priv->pdev->dev, "Parity Error\n");
+	if (lsr & UART_LSR_PE) {
+		port->icount.parity++;
+		error_msg[i++] = "  Parity Error\n";
+	}
 
-	if (lsr & UART_LSR_OE)
-		dev_err(&priv->pdev->dev, "Overrun Error\n");
+	if (lsr & UART_LSR_OE) {
+		port->icount.overrun++;
+		error_msg[i++] = "  Overrun Error\n";
+	}
+
+	if (tty == NULL) {
+		for (i = 0; error_msg[i] != NULL; i++)
+			dev_err(&priv->pdev->dev, error_msg[i]);
+	}
 }
 
 static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)
diff --git a/fs/exec.c b/fs/exec.c
index 3801daf..9ab31ca 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1149,13 +1149,6 @@ void setup_new_exec(struct linux_binprm * bprm)
 		set_dumpable(current->mm, suid_dumpable);
 	}
 
-	/*
-	 * Flush performance counters when crossing a
-	 * security domain:
-	 */
-	if (!get_dumpable(current->mm))
-		perf_event_exit_task(current);
-
 	/* An exec changes our domain. We are no longer part of the thread
 	   group */
 
@@ -1219,6 +1212,15 @@ void install_exec_creds(struct linux_binprm *bprm)
 
 	commit_creds(bprm->cred);
 	bprm->cred = NULL;
+
+	/*
+	 * Disable monitoring for regular users
+	 * when executing setuid binaries. Must
+	 * wait until new credentials are committed
+	 * by commit_creds() above
+	 */
+	if (get_dumpable(current->mm) != SUID_DUMP_USER)
+		perf_event_exit_task(current);
 	/*
 	 * cred_guard_mutex must be held at least to this point to prevent
 	 * ptrace_attach() from altering our determination of the task's
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index ef5abd3..936a038 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -355,31 +355,50 @@ static unsigned int vfs_dent_type(uint8_t type)
 static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
 {
 	int err, over = 0;
+	loff_t pos = file->f_pos;
 	struct qstr nm;
 	union ubifs_key key;
 	struct ubifs_dent_node *dent;
 	struct inode *dir = file->f_path.dentry->d_inode;
 	struct ubifs_info *c = dir->i_sb->s_fs_info;
 
-	dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
+	dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, pos);
 
-	if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2)
+	if (pos > UBIFS_S_KEY_HASH_MASK || pos == 2)
 		/*
 		 * The directory was seek'ed to a senseless position or there
 		 * are no more entries.
 		 */
 		return 0;
 
+	if (file->f_version == 0) {
+		/*
+		 * The file was seek'ed, which means that @file->private_data
+		 * is now invalid. This may also be just the first
+		 * 'ubifs_readdir()' invocation, in which case
+		 * @file->private_data is NULL, and the below code is
+		 * basically a no-op.
+		 */
+		kfree(file->private_data);
+		file->private_data = NULL;
+	}
+
+	/*
+	 * 'generic_file_llseek()' unconditionally sets @file->f_version to
+	 * zero, and we use this for detecting whether the file was seek'ed.
+	 */
+	file->f_version = 1;
+
 	/* File positions 0 and 1 correspond to "." and ".." */
-	if (file->f_pos == 0) {
+	if (pos == 0) {
 		ubifs_assert(!file->private_data);
 		over = filldir(dirent, ".", 1, 0, dir->i_ino, DT_DIR);
 		if (over)
 			return 0;
-		file->f_pos = 1;
+		file->f_pos = pos = 1;
 	}
 
-	if (file->f_pos == 1) {
+	if (pos == 1) {
 		ubifs_assert(!file->private_data);
 		over = filldir(dirent, "..", 2, 1,
 			       parent_ino(file->f_path.dentry), DT_DIR);
@@ -395,7 +414,7 @@ static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
 			goto out;
 		}
 
-		file->f_pos = key_hash_flash(c, &dent->key);
+		file->f_pos = pos = key_hash_flash(c, &dent->key);
 		file->private_data = dent;
 	}
 
@@ -403,17 +422,16 @@ static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
 	if (!dent) {
 		/*
 		 * The directory was seek'ed to and is now readdir'ed.
-		 * Find the entry corresponding to @file->f_pos or the
-		 * closest one.
+		 * Find the entry corresponding to @pos or the closest one.
 		 */
-		dent_key_init_hash(c, &key, dir->i_ino, file->f_pos);
+		dent_key_init_hash(c, &key, dir->i_ino, pos);
 		nm.name = NULL;
 		dent = ubifs_tnc_next_ent(c, &key, &nm);
 		if (IS_ERR(dent)) {
 			err = PTR_ERR(dent);
 			goto out;
 		}
-		file->f_pos = key_hash_flash(c, &dent->key);
+		file->f_pos = pos = key_hash_flash(c, &dent->key);
 		file->private_data = dent;
 	}
 
@@ -425,7 +443,7 @@ static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
 			     ubifs_inode(dir)->creat_sqnum);
 
 		nm.len = le16_to_cpu(dent->nlen);
-		over = filldir(dirent, dent->name, nm.len, file->f_pos,
+		over = filldir(dirent, dent->name, nm.len, pos,
 			       le64_to_cpu(dent->inum),
 			       vfs_dent_type(dent->type));
 		if (over)
@@ -441,9 +459,17 @@ static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
 		}
 
 		kfree(file->private_data);
-		file->f_pos = key_hash_flash(c, &dent->key);
+		file->f_pos = pos = key_hash_flash(c, &dent->key);
 		file->private_data = dent;
 		cond_resched();
+
+		if (file->f_version == 0)
+			/*
+			 * The file was seek'ed meanwhile, lets return and start
+			 * reading direntries from the new position on the next
+			 * invocation.
+			 */
+			return 0;
 	}
 
 out:
@@ -454,15 +480,13 @@ out:
 
 	kfree(file->private_data);
 	file->private_data = NULL;
+	/* 2 is a special value indicating that there are no more direntries */
 	file->f_pos = 2;
 	return 0;
 }
 
-/* If a directory is seeked, we have to free saved readdir() state */
 static loff_t ubifs_dir_llseek(struct file *file, loff_t offset, int origin)
 {
-	kfree(file->private_data);
-	file->private_data = NULL;
 	return generic_file_llseek(file, offset, origin);
 }
 
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index 086adf2..d99cb4b 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -147,7 +147,7 @@ fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp,
 		return;
 	}
 
-	for_each_online_cpu(cpu) {
+	for_each_possible_cpu(cpu) {
 		unsigned int nr;
 
 		nr = per_cpu(nr_cpu_bp_pinned[type], cpu);
@@ -233,7 +233,7 @@ toggle_bp_slot(struct perf_event *bp, bool enable, enum bp_type_idx type,
 	if (cpu >= 0) {
 		toggle_bp_task_slot(bp, cpu, enable, type, weight);
 	} else {
-		for_each_online_cpu(cpu)
+		for_each_possible_cpu(cpu)
 			toggle_bp_task_slot(bp, cpu, enable, type, weight);
 	}
 
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 7705e26..2a74877 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -1514,6 +1514,9 @@ static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
 	BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %d",
 			conn, code, ident, dlen);
 
+	if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
+		return NULL;
+
 	len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
 	count = min_t(unsigned int, conn->mtu, len);
 
