lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <55C2029D.30003@maciej.szmigiero.name>
Date:	Wed, 05 Aug 2015 14:33:33 +0200
From:	"Maciej S. Szmigiero" <mail@...iej.szmigiero.name>
To:	linux-serial@...r.kernel.org
CC:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Jiri Slaby <jslaby@...e.com>,
	linux-kernel <linux-kernel@...r.kernel.org>
Subject: [PATCH] serial: don't register CIR serial ports

CIR type serial ports aren't real serial ports.

This is just a way to prevent legacy 8250 serial
driver from probing and eventually binding some
resources.

Since in current state such ports aren't providing
any real functionality and it is not possible
to change their type via setserial/ioctl(TIOCSSERIAL)
(due to UPF_FIXED_PORT flag set on them)
it is simpler and cleaner to not register them at all
with serial core.

Print a short message in this case so it is known
to user what has happened.

This way checks for PORT_8250_CIR in serial port
callbacks can be removed too, since they won't
ever be called.

Signed-off-by: Maciej Szmigiero <mail@...iej.szmigiero.name>
---
This replaces "serial: don't announce CIR serial ports"
submission.

 drivers/tty/serial/8250/8250_core.c |   38 +++++++++++++++++-----------------
 1 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 37fff12..b843b83 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -2129,9 +2129,6 @@ int serial8250_do_startup(struct uart_port *port)
 	unsigned char lsr, iir;
 	int retval;
 
-	if (port->type == PORT_8250_CIR)
-		return -ENODEV;
-
 	if (!port->fifosize)
 		port->fifosize = uart_config[port->type].fifo_size;
 	if (!up->tx_loadsz)
@@ -2858,14 +2855,8 @@ static void serial8250_release_port(struct uart_port *port)
 static int serial8250_request_port(struct uart_port *port)
 {
 	struct uart_8250_port *up = up_to_u8250p(port);
-	int ret;
-
-	if (port->type == PORT_8250_CIR)
-		return -ENODEV;
-
-	ret = serial8250_request_std_resource(up);
 
-	return ret;
+	return serial8250_request_std_resource(up);
 }
 
 static int fcr_get_rxtrig_bytes(struct uart_8250_port *up)
@@ -3013,9 +3004,6 @@ static void serial8250_config_port(struct uart_port *port, int flags)
 	struct uart_8250_port *up = up_to_u8250p(port);
 	int ret;
 
-	if (port->type == PORT_8250_CIR)
-		return;
-
 	/*
 	 * Find the region that we can probe for.  This in turn
 	 * tells us whether we can probe for the type of port.
@@ -3889,13 +3877,25 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
 		if (up->dl_write)
 			uart->dl_write = up->dl_write;
 
-		if (serial8250_isa_config != NULL)
-			serial8250_isa_config(0, &uart->port,
-					&uart->capabilities);
+		if (uart->port.type != PORT_8250_CIR) {
+			if (serial8250_isa_config != NULL)
+				serial8250_isa_config(0, &uart->port,
+						&uart->capabilities);
 
-		ret = uart_add_one_port(&serial8250_reg, &uart->port);
-		if (ret == 0)
-			ret = uart->port.line;
+			ret = uart_add_one_port(&serial8250_reg,
+						&uart->port);
+			if (ret == 0)
+				ret = uart->port.line;
+		} else {
+			pr_info("%s%sskipping CIR port at 0x%lx / 0x%llx, IRQ %d\n",
+				uart->port.dev ? dev_name(uart->port.dev) : "",
+				uart->port.dev ? ": " : "",
+				uart->port.iobase,
+				(unsigned long long)uart->port.mapbase,
+				uart->port.irq);
+
+			ret = 0;
+		}
 	}
 	mutex_unlock(&serial_mutex);
 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ