Merge tag 'tty-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some tty and serial driver fixes for 5.7-rc3.

  The "largest" in here are a number of reverts for previous changes to
  the uartps serial driver that turned out to not be a good idea at all.

  The others are just small fixes found by people and tools. Included in
  here is a much-reported symbol export needed by previous changes that
  happened in 5.7-rc1. All of these have been in linux-next for a while
  with no reported issues"

* tag 'tty-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: hvc: fix buffer overflow during hvc_alloc().
  tty: rocket, avoid OOB access
  tty: serial: bcm63xx: fix missing clk_put() in bcm63xx_uart
  vt: don't hardcode the mem allocation upper bound
  tty: serial: owl: add "much needed" clk_prepare_enable()
  vt: don't use kmalloc() for the unicode screen buffer
  tty/sysrq: Export sysrq_mask(), sysrq_toggle_support()
  serial: sh-sci: Make sure status register SCxSR is read in correct sequence
  serial: sunhv: Initialize lock for non-registered console
  Revert "serial: uartps: Register own uart console and driver structures"
  Revert "serial: uartps: Move Port ID to device data structure"
  Revert "serial: uartps: Change uart ID port allocation"
  Revert "serial: uartps: Do not allow use aliases >= MAX_UART_INSTANCES"
  Revert "serial: uartps: Fix error path when alloc failed"
  Revert "serial: uartps: Use the same dynamic major number for all ports"
  Revert "serial: uartps: Fix uartps_major handling"

drivers/tty/hvc/hvc_console.c

@@ -302,10 +302,6 @@ int hvc_instantiate(uint32_t vtermno, int index, const struct hv_ops *ops)
 	vtermnos[index] = vtermno;
 	cons_ops[index] = ops;
 
-	/* reserve all indices up to and including this index */
-	if (last_hvc < index)
-		last_hvc = index;
-
 	/* check if we need to re-register the kernel console */
 	hvc_check_console(index);
 
@@ -960,13 +956,22 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
 		    cons_ops[i] == hp->ops)
 			break;
 
-	/* no matching slot, just use a counter */
-	if (i >= MAX_NR_HVC_CONSOLES)
-		i = ++last_hvc;
+	if (i >= MAX_NR_HVC_CONSOLES) {
+
+		/* find 'empty' slot for console */
+		for (i = 0; i < MAX_NR_HVC_CONSOLES && vtermnos[i] != -1; i++) {
+		}
+
+		/* no matching slot, just use a counter */
+		if (i == MAX_NR_HVC_CONSOLES)
+			i = ++last_hvc + MAX_NR_HVC_CONSOLES;
+	}
 
 	hp->index = i;
-	cons_ops[i] = ops;
-	vtermnos[i] = vtermno;
+	if (i < MAX_NR_HVC_CONSOLES) {
+		cons_ops[i] = ops;
+		vtermnos[i] = vtermno;
+	}
 
 	list_add_tail(&(hp->next), &hvc_structs);
 	mutex_unlock(&hvc_structs_mutex);

drivers/tty/rocket.c

@@ -632,18 +632,21 @@ init_r_port(int board, int aiop, int chan, struct pci_dev *pci_dev)
 	tty_port_init(&info->port);
 	info->port.ops = &rocket_port_ops;
 	info->flags &= ~ROCKET_MODE_MASK;
-	switch (pc104[board][line]) {
-	case 422:
-		info->flags |= ROCKET_MODE_RS422;
-		break;
-	case 485:
-		info->flags |= ROCKET_MODE_RS485;
-		break;
-	case 232:
-	default:
+	if (board < ARRAY_SIZE(pc104) && line < ARRAY_SIZE(pc104_1))
+		switch (pc104[board][line]) {
+		case 422:
+			info->flags |= ROCKET_MODE_RS422;
+			break;
+		case 485:
+			info->flags |= ROCKET_MODE_RS485;
+			break;
+		case 232:
+		default:
+			info->flags |= ROCKET_MODE_RS232;
+			break;
+		}
+	else
 		info->flags |= ROCKET_MODE_RS232;
-		break;
-	}
 
 	info->intmask = RXF_TRIG | TXFIFO_MT | SRC_INT | DELTA_CD | DELTA_CTS | DELTA_DSR;
 	if (sInitChan(ctlp, &info->channel, aiop, chan) == 0) {

drivers/tty/serial/bcm63xx_uart.c

@@ -843,8 +843,10 @@ static int bcm_uart_probe(struct platform_device *pdev)
 	if (IS_ERR(clk) && pdev->dev.of_node)
 		clk = of_clk_get(pdev->dev.of_node, 0);
 
-	if (IS_ERR(clk))
+	if (IS_ERR(clk)) {
+		clk_put(clk);
 		return -ENODEV;
+	}
 
 	port->iotype = UPIO_MEM;
 	port->irq = res_irq->start;

drivers/tty/serial/owl-uart.c

@@ -680,6 +680,12 @@ static int owl_uart_probe(struct platform_device *pdev)
 		return PTR_ERR(owl_port->clk);
 	}
 
+	ret = clk_prepare_enable(owl_port->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "could not enable clk\n");
+		return ret;
+	}
+
 	owl_port->port.dev = &pdev->dev;
 	owl_port->port.line = pdev->id;
 	owl_port->port.type = PORT_OWL;
@@ -712,6 +718,7 @@ static int owl_uart_remove(struct platform_device *pdev)
 
 	uart_remove_one_port(&owl_uart_driver, &owl_port->port);
 	owl_uart_ports[pdev->id] = NULL;
+	clk_disable_unprepare(owl_port->clk);
 
 	return 0;
 }

drivers/tty/serial/sh-sci.c

@@ -870,9 +870,16 @@ static void sci_receive_chars(struct uart_port *port)
 				tty_insert_flip_char(tport, c, TTY_NORMAL);
 		} else {
 			for (i = 0; i < count; i++) {
-				char c = serial_port_in(port, SCxRDR);
-
-				status = serial_port_in(port, SCxSR);
+				char c;
+
+				if (port->type == PORT_SCIF ||
+				    port->type == PORT_HSCIF) {
+					status = serial_port_in(port, SCxSR);
+					c = serial_port_in(port, SCxRDR);
+				} else {
+					c = serial_port_in(port, SCxRDR);
+					status = serial_port_in(port, SCxSR);
+				}
 				if (uart_handle_sysrq_char(port, c)) {
 					count--; i--;
 					continue;

drivers/tty/serial/sunhv.c

@@ -567,6 +567,9 @@ static int hv_probe(struct platform_device *op)
 	sunserial_console_match(&sunhv_console, op->dev.of_node,
 				&sunhv_reg, port->line, false);
 
+	/* We need to initialize lock even for non-registered console */
+	spin_lock_init(&port->lock);
+
 	err = uart_add_one_port(&sunhv_reg, port);
 	if (err)
 		goto out_unregister_driver;

drivers/tty/serial/xilinx_uartps.c

@@ -26,13 +26,15 @@
 
 #define CDNS_UART_TTY_NAME	"ttyPS"
 #define CDNS_UART_NAME		"xuartps"
+#define CDNS_UART_MAJOR		0	/* use dynamic node allocation */
+#define CDNS_UART_MINOR		0	/* works best with devtmpfs */
+#define CDNS_UART_NR_PORTS	16
 #define CDNS_UART_FIFO_SIZE	64	/* FIFO size */
 #define CDNS_UART_REGISTER_SPACE	0x1000
 #define TX_TIMEOUT		500000
 
 /* Rx Trigger level */
 static int rx_trigger_level = 56;
-static int uartps_major;
 module_param(rx_trigger_level, uint, 0444);
 MODULE_PARM_DESC(rx_trigger_level, "Rx trigger level, 1-63 bytes");
 
@@ -188,7 +190,6 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
  * @pclk:		APB clock
  * @cdns_uart_driver:	Pointer to UART driver
  * @baud:		Current baud rate
- * @id:			Port ID
  * @clk_rate_change_nb:	Notifier block for clock changes
  * @quirks:		Flags for RXBS support.
  */
@@ -198,7 +199,6 @@ struct cdns_uart {
 	struct clk		*pclk;
 	struct uart_driver	*cdns_uart_driver;
 	unsigned int		baud;
-	int			id;
 	struct notifier_block	clk_rate_change_nb;
 	u32			quirks;
 	bool cts_override;
@@ -1133,6 +1133,8 @@ static const struct uart_ops cdns_uart_ops = {
 #endif
 };
 
+static struct uart_driver cdns_uart_uart_driver;
+
 #ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
 /**
  * cdns_uart_console_putchar - write the character to the FIFO buffer
@@ -1272,6 +1274,16 @@ static int cdns_uart_console_setup(struct console *co, char *options)
 
 	return uart_set_options(port, co, baud, parity, bits, flow);
 }
+
+static struct console cdns_uart_console = {
+	.name	= CDNS_UART_TTY_NAME,
+	.write	= cdns_uart_console_write,
+	.device	= uart_console_device,
+	.setup	= cdns_uart_console_setup,
+	.flags	= CON_PRINTBUFFER,
+	.index	= -1, /* Specified on the cmdline (e.g. console=ttyPS ) */
+	.data	= &cdns_uart_uart_driver,
+};
 #endif /* CONFIG_SERIAL_XILINX_PS_UART_CONSOLE */
 
 #ifdef CONFIG_PM_SLEEP
@@ -1403,89 +1415,8 @@ static const struct of_device_id cdns_uart_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, cdns_uart_of_match);
 
-/*
- * Maximum number of instances without alias IDs but if there is alias
- * which target "< MAX_UART_INSTANCES" range this ID can't be used.
- */
-#define MAX_UART_INSTANCES	32
-
-/* Stores static aliases list */
-static DECLARE_BITMAP(alias_bitmap, MAX_UART_INSTANCES);
-static int alias_bitmap_initialized;
-
-/* Stores actual bitmap of allocated IDs with alias IDs together */
-static DECLARE_BITMAP(bitmap, MAX_UART_INSTANCES);
-/* Protect bitmap operations to have unique IDs */
-static DEFINE_MUTEX(bitmap_lock);
-
-static int cdns_get_id(struct platform_device *pdev)
-{
-	int id, ret;
-
-	mutex_lock(&bitmap_lock);
-
-	/* Alias list is stable that's why get alias bitmap only once */
-	if (!alias_bitmap_initialized) {
-		ret = of_alias_get_alias_list(cdns_uart_of_match, "serial",
-					      alias_bitmap, MAX_UART_INSTANCES);
-		if (ret && ret != -EOVERFLOW) {
-			mutex_unlock(&bitmap_lock);
-			return ret;
-		}
-
-		alias_bitmap_initialized++;
-	}
-
-	/* Make sure that alias ID is not taken by instance without alias */
-	bitmap_or(bitmap, bitmap, alias_bitmap, MAX_UART_INSTANCES);
-
-	dev_dbg(&pdev->dev, "Alias bitmap: %*pb\n",
-		MAX_UART_INSTANCES, bitmap);
-
-	/* Look for a serialN alias */
-	id = of_alias_get_id(pdev->dev.of_node, "serial");
-	if (id < 0) {
-		dev_warn(&pdev->dev,
-			 "No serial alias passed. Using the first free id\n");
-
-		/*
-		 * Start with id 0 and check if there is no serial0 alias
-		 * which points to device which is compatible with this driver.
-		 * If alias exists then try next free position.
-		 */
-		id = 0;
-
-		for (;;) {
-			dev_info(&pdev->dev, "Checking id %d\n", id);
-			id = find_next_zero_bit(bitmap, MAX_UART_INSTANCES, id);
-
-			/* No free empty instance */
-			if (id == MAX_UART_INSTANCES) {
-				dev_err(&pdev->dev, "No free ID\n");
-				mutex_unlock(&bitmap_lock);
-				return -EINVAL;
-			}
-
-			dev_dbg(&pdev->dev, "The empty id is %d\n", id);
-			/* Check if ID is empty */
-			if (!test_and_set_bit(id, bitmap)) {
-				/* Break the loop if bit is taken */
-				dev_dbg(&pdev->dev,
-					"Selected ID %d allocation passed\n",
-					id);
-				break;
-			}
-			dev_dbg(&pdev->dev,
-				"Selected ID %d allocation failed\n", id);
-			/* if taking bit fails then try next one */
-			id++;
-		}
-	}
-
-	mutex_unlock(&bitmap_lock);
-
-	return id;
-}
+/* Temporary variable for storing number of instances */
+static int instances;
 
 /**
  * cdns_uart_probe - Platform driver probe
@@ -1495,16 +1426,11 @@ static int cdns_get_id(struct platform_device *pdev)
  */
 static int cdns_uart_probe(struct platform_device *pdev)
 {
-	int rc, irq;
+	int rc, id, irq;
 	struct uart_port *port;
 	struct resource *res;
 	struct cdns_uart *cdns_uart_data;
 	const struct of_device_id *match;
-	struct uart_driver *cdns_uart_uart_driver;
-	char *driver_name;
-#ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
-	struct console *cdns_uart_console;
-#endif
 
 	cdns_uart_data = devm_kzalloc(&pdev->dev, sizeof(*cdns_uart_data),
 			GFP_KERNEL);
@@ -1514,64 +1440,35 @@ static int cdns_uart_probe(struct platform_device *pdev)
 	if (!port)
 		return -ENOMEM;
 
-	cdns_uart_uart_driver = devm_kzalloc(&pdev->dev,
-					     sizeof(*cdns_uart_uart_driver),
-					     GFP_KERNEL);
-	if (!cdns_uart_uart_driver)
-		return -ENOMEM;
-
-	cdns_uart_data->id = cdns_get_id(pdev);
-	if (cdns_uart_data->id < 0)
-		return cdns_uart_data->id;
+	/* Look for a serialN alias */
+	id = of_alias_get_id(pdev->dev.of_node, "serial");
+	if (id < 0)
+		id = 0;
 
-	/* There is a need to use unique driver name */
-	driver_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%s%d",
-				     CDNS_UART_NAME, cdns_uart_data->id);
-	if (!driver_name) {
-		rc = -ENOMEM;
-		goto err_out_id;
+	if (id >= CDNS_UART_NR_PORTS) {
+		dev_err(&pdev->dev, "Cannot get uart_port structure\n");
+		return -ENODEV;
 	}
 
-	cdns_uart_uart_driver->owner = THIS_MODULE;
-	cdns_uart_uart_driver->driver_name = driver_name;
-	cdns_uart_uart_driver->dev_name	= CDNS_UART_TTY_NAME;
-	cdns_uart_uart_driver->major = uartps_major;
-	cdns_uart_uart_driver->minor = cdns_uart_data->id;
-	cdns_uart_uart_driver->nr = 1;
-
+	if (!cdns_uart_uart_driver.state) {
+		cdns_uart_uart_driver.owner = THIS_MODULE;
+		cdns_uart_uart_driver.driver_name = CDNS_UART_NAME;
+		cdns_uart_uart_driver.dev_name = CDNS_UART_TTY_NAME;
+		cdns_uart_uart_driver.major = CDNS_UART_MAJOR;
+		cdns_uart_uart_driver.minor = CDNS_UART_MINOR;
+		cdns_uart_uart_driver.nr = CDNS_UART_NR_PORTS;
 #ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
-	cdns_uart_console = devm_kzalloc(&pdev->dev, sizeof(*cdns_uart_console),
-					 GFP_KERNEL);
-	if (!cdns_uart_console) {
-		rc = -ENOMEM;
-		goto err_out_id;
-	}
-
-	strncpy(cdns_uart_console->name, CDNS_UART_TTY_NAME,
-		sizeof(cdns_uart_console->name));
-	cdns_uart_console->index = cdns_uart_data->id;
-	cdns_uart_console->write = cdns_uart_console_write;
-	cdns_uart_console->device = uart_console_device;
-	cdns_uart_console->setup = cdns_uart_console_setup;
-	cdns_uart_console->flags = CON_PRINTBUFFER;
-	cdns_uart_console->data = cdns_uart_uart_driver;
-	cdns_uart_uart_driver->cons = cdns_uart_console;
+		cdns_uart_uart_driver.cons = &cdns_uart_console;
 #endif
 
-	rc = uart_register_driver(cdns_uart_uart_driver);
-	if (rc < 0) {
-		dev_err(&pdev->dev, "Failed to register driver\n");
-		goto err_out_id;
+		rc = uart_register_driver(&cdns_uart_uart_driver);
+		if (rc < 0) {
+			dev_err(&pdev->dev, "Failed to register driver\n");
+			return rc;
+		}
 	}
 
-	cdns_uart_data->cdns_uart_driver = cdns_uart_uart_driver;
-
-	/*
-	 * Setting up proper name_base needs to be done after uart
-	 * registration because tty_driver structure is not filled.
-	 * name_base is 0 by default.
-	 */
-	cdns_uart_uart_driver->tty_driver->name_base = cdns_uart_data->id;
+	cdns_uart_data->cdns_uart_driver = &cdns_uart_uart_driver;
 
 	match = of_match_node(cdns_uart_of_match, pdev->dev.of_node);
 	if (match && match->data) {
@@ -1649,6 +1546,7 @@ static int cdns_uart_probe(struct platform_device *pdev)
 	port->ops	= &cdns_uart_ops;
 	port->fifosize	= CDNS_UART_FIFO_SIZE;
 	port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_XILINX_PS_UART_CONSOLE);
+	port->line	= id;
 
 	/*
 	 * Register the port.
@@ -1680,7 +1578,7 @@ static int cdns_uart_probe(struct platform_device *pdev)
 		console_port = port;
 #endif
 
-	rc = uart_add_one_port(cdns_uart_uart_driver, port);
+	rc = uart_add_one_port(&cdns_uart_uart_driver, port);
 	if (rc) {
 		dev_err(&pdev->dev,
 			"uart_add_one_port() failed; err=%i\n", rc);
@@ -1690,13 +1588,15 @@ static int cdns_uart_probe(struct platform_device *pdev)
 #ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
 	/* This is not port which is used for console that's why clean it up */
 	if (console_port == port &&
-	    !(cdns_uart_uart_driver->cons->flags & CON_ENABLED))
+	    !(cdns_uart_uart_driver.cons->flags & CON_ENABLED))
 		console_port = NULL;
 #endif
 
-	uartps_major = cdns_uart_uart_driver->tty_driver->major;
 	cdns_uart_data->cts_override = of_property_read_bool(pdev->dev.of_node,
 							     "cts-override");
+
+	instances++;
+
 	return 0;
 
 err_out_pm_disable:
@@ -1712,12 +1612,8 @@ static int cdns_uart_probe(struct platform_device *pdev)
 err_out_clk_dis_pclk:
 	clk_disable_unprepare(cdns_uart_data->pclk);
 err_out_unregister_driver:
-	uart_unregister_driver(cdns_uart_data->cdns_uart_driver);
-err_out_id:
-	mutex_lock(&bitmap_lock);
-	if (cdns_uart_data->id < MAX_UART_INSTANCES)
-		clear_bit(cdns_uart_data->id, bitmap);
-	mutex_unlock(&bitmap_lock);
+	if (!instances)
+		uart_unregister_driver(cdns_uart_data->cdns_uart_driver);
 	return rc;
 }
 
@@ -1740,10 +1636,6 @@ static int cdns_uart_remove(struct platform_device *pdev)
 #endif
 	rc = uart_remove_one_port(cdns_uart_data->cdns_uart_driver, port);
 	port->mapbase = 0;
-	mutex_lock(&bitmap_lock);
-	if (cdns_uart_data->id < MAX_UART_INSTANCES)
-		clear_bit(cdns_uart_data->id, bitmap);
-	mutex_unlock(&bitmap_lock);
 	clk_disable_unprepare(cdns_uart_data->uartclk);
 	clk_disable_unprepare(cdns_uart_data->pclk);
 	pm_runtime_disable(&pdev->dev);
@@ -1756,13 +1648,8 @@ static int cdns_uart_remove(struct platform_device *pdev)
 		console_port = NULL;
 #endif
 
-	/* If this is last instance major number should be initialized */
-	mutex_lock(&bitmap_lock);
-	if (bitmap_empty(bitmap, MAX_UART_INSTANCES))
-		uartps_major = 0;
-	mutex_unlock(&bitmap_lock);
-
-	uart_unregister_driver(cdns_uart_data->cdns_uart_driver);
+	if (!--instances)
+		uart_unregister_driver(cdns_uart_data->cdns_uart_driver);
 	return rc;
 }
 

drivers/tty/sysrq.c

@@ -74,6 +74,7 @@ int sysrq_mask(void)
 		return 1;
 	return sysrq_enabled;
 }
+EXPORT_SYMBOL_GPL(sysrq_mask);
 
 /*
  * A value of 1 means 'all', other nonzero values are an op mask:
@@ -1058,6 +1059,7 @@ int sysrq_toggle_support(int enable_mask)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(sysrq_toggle_support);
 
 static int __sysrq_swap_key_ops(int key, struct sysrq_key_op *insert_op_p,
                                 struct sysrq_key_op *remove_op_p)

drivers/tty/vt/vt.c

@@ -81,6 +81,7 @@
 #include <linux/errno.h>
 #include <linux/kd.h>
 #include <linux/slab.h>
+#include <linux/vmalloc.h>
 #include <linux/major.h>
 #include <linux/mm.h>
 #include <linux/console.h>
@@ -350,7 +351,7 @@ static struct uni_screen *vc_uniscr_alloc(unsigned int cols, unsigned int rows)
 	/* allocate everything in one go */
 	memsize = cols * rows * sizeof(char32_t);
 	memsize += rows * sizeof(char32_t *);
-	p = kmalloc(memsize, GFP_KERNEL);
+	p = vmalloc(memsize);
 	if (!p)
 		return NULL;
 
@@ -366,7 +367,7 @@ static struct uni_screen *vc_uniscr_alloc(unsigned int cols, unsigned int rows)
 
 static void vc_uniscr_set(struct vc_data *vc, struct uni_screen *new_uniscr)
 {
-	kfree(vc->vc_uni_screen);
+	vfree(vc->vc_uni_screen);
 	vc->vc_uni_screen = new_uniscr;
 }
 
@@ -1206,7 +1207,7 @@ static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
 	if (new_cols == vc->vc_cols && new_rows == vc->vc_rows)
 		return 0;
 
-	if (new_screen_size > (4 << 20))
+	if (new_screen_size > KMALLOC_MAX_SIZE)
 		return -EINVAL;
 	newscreen = kzalloc(new_screen_size, GFP_USER);
 	if (!newscreen)