* [PATCH 1/5] vt: fix issue when fbcon wants to takeover a second time.
2011-01-31 16:28 [GIT PATCH] TTY/serial driver fixes for .38 Greg KH
@ 2011-01-31 16:31 ` Greg Kroah-Hartman
2011-01-31 16:31 ` [PATCH 2/5] tty: use for_each_console() and WARN() on sysfs failures Greg Kroah-Hartman
` (3 subsequent siblings)
4 siblings, 0 replies; 8+ messages in thread
From: Greg Kroah-Hartman @ 2011-01-31 16:31 UTC (permalink / raw)
To: linux-kernel; +Cc: Dave Airlie, Alan Cox, Greg Kroah-Hartman
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 1554 bytes --]
From: Dave Airlie <airlied@redhat.com>
With framebuffer handover and multiple GPUs, we get into a
position where the fbcon unbinds the vesafb framebuffer for GPU 1,
but we still have a radeon framebuffer bound from GPU 0, so
we don't unregister the console driver. Then when we tried to bind
the new radeon framebuffer for GPU1 we never get to the bind
call as we fail due to the console being registered already.
This changes the return value to -EBUSY when the driver is
already registered and continues to bind for -EBUSY.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/tty/vt/vt.c | 9 +++++++--
1 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 76407ec..4f6ae05 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -3545,7 +3545,7 @@ int register_con_driver(const struct consw *csw, int first, int last)
/* already registered */
if (con_driver->con == csw)
- retval = -EINVAL;
+ retval = -EBUSY;
}
if (retval)
@@ -3656,7 +3656,12 @@ int take_over_console(const struct consw *csw, int first, int last, int deflt)
int err;
err = register_con_driver(csw, first, last);
-
+ /* if we get an busy error we still want to bind the console driver
+ * and return success, as we may have unbound the console driver
+ * but not unregistered it.
+ */
+ if (err == -EBUSY)
+ err = 0;
if (!err)
bind_con_driver(csw, first, last, deflt);
--
1.7.1
^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH 2/5] tty: use for_each_console() and WARN() on sysfs failures
2011-01-31 16:28 [GIT PATCH] TTY/serial driver fixes for .38 Greg KH
2011-01-31 16:31 ` [PATCH 1/5] vt: fix issue when fbcon wants to takeover a second time Greg Kroah-Hartman
@ 2011-01-31 16:31 ` Greg Kroah-Hartman
2011-01-31 16:31 ` [PATCH 3/5] serial: unbreak billionton CF card Greg Kroah-Hartman
` (2 subsequent siblings)
4 siblings, 0 replies; 8+ messages in thread
From: Greg Kroah-Hartman @ 2011-01-31 16:31 UTC (permalink / raw)
To: linux-kernel; +Cc: Kay Sievers, Greg Kroah-Hartman
From: Kay Sievers <kay.sievers@vrfy.org>
This fixes the build warnings in the tty code, and uses the proper
function for iterating over the console devices.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/tty/tty_io.c | 4 ++--
drivers/tty/vt/vt.c | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 464d09d..dae6fc9 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -3257,7 +3257,7 @@ static ssize_t show_cons_active(struct device *dev,
ssize_t count = 0;
acquire_console_sem();
- for (c = console_drivers; c; c = c->next) {
+ for_each_console(c) {
if (!c->device)
continue;
if (!c->write)
@@ -3306,7 +3306,7 @@ int __init tty_init(void)
if (IS_ERR(consdev))
consdev = NULL;
else
- device_create_file(consdev, &dev_attr_active);
+ WARN_ON(device_create_file(consdev, &dev_attr_active) < 0);
#ifdef CONFIG_VT
vty_init(&console_fops);
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 4f6ae05..9550618 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -2994,7 +2994,7 @@ int __init vty_init(const struct file_operations *console_fops)
if (IS_ERR(tty0dev))
tty0dev = NULL;
else
- device_create_file(tty0dev, &dev_attr_active);
+ WARN_ON(device_create_file(tty0dev, &dev_attr_active) < 0);
vcs_init();
--
1.7.1
^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH 3/5] serial: unbreak billionton CF card
2011-01-31 16:28 [GIT PATCH] TTY/serial driver fixes for .38 Greg KH
2011-01-31 16:31 ` [PATCH 1/5] vt: fix issue when fbcon wants to takeover a second time Greg Kroah-Hartman
2011-01-31 16:31 ` [PATCH 2/5] tty: use for_each_console() and WARN() on sysfs failures Greg Kroah-Hartman
@ 2011-01-31 16:31 ` Greg Kroah-Hartman
2011-01-31 21:48 ` Alan Cox
2011-01-31 16:31 ` [PATCH 4/5] n_hdlc: fix read and write locking Greg Kroah-Hartman
2011-01-31 16:31 ` [PATCH 5/5] tty/serial: fix apbuart build Greg Kroah-Hartman
4 siblings, 1 reply; 8+ messages in thread
From: Greg Kroah-Hartman @ 2011-01-31 16:31 UTC (permalink / raw)
To: linux-kernel; +Cc: Pavel Machek, stable, Greg Kroah-Hartman
From: Pavel Machek <pavel@ucw.cz>
Unbreak Billionton CF bluetooth card. This actually fixes a regression
on zaurus.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/tty/serial/8250.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c
index b25e6e4..3975df6 100644
--- a/drivers/tty/serial/8250.c
+++ b/drivers/tty/serial/8250.c
@@ -236,7 +236,8 @@ static const struct serial8250_config uart_config[] = {
.fifo_size = 128,
.tx_loadsz = 128,
.fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
- .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP,
+ /* UART_CAP_EFR breaks billionon CF bluetooth card. */
+ .flags = UART_CAP_FIFO | UART_CAP_SLEEP,
},
[PORT_16654] = {
.name = "ST16654",
--
1.7.1
^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH 4/5] n_hdlc: fix read and write locking
2011-01-31 16:28 [GIT PATCH] TTY/serial driver fixes for .38 Greg KH
` (2 preceding siblings ...)
2011-01-31 16:31 ` [PATCH 3/5] serial: unbreak billionton CF card Greg Kroah-Hartman
@ 2011-01-31 16:31 ` Greg Kroah-Hartman
2011-01-31 16:31 ` [PATCH 5/5] tty/serial: fix apbuart build Greg Kroah-Hartman
4 siblings, 0 replies; 8+ messages in thread
From: Greg Kroah-Hartman @ 2011-01-31 16:31 UTC (permalink / raw)
To: linux-kernel; +Cc: Paul Fulghum, Alan Cox, Andrew Morton, Greg Kroah-Hartman
From: Paul Fulghum <paulkf@microgate.com>
Fix locking in read and write code of n_hdlc line discipline.
2.6.36 replaced lock_kernel() with tty_lock(). The tty mutex is not
dropped automatically when the thread sleeps like the BKL. This results
in a blocked read or write holding the tty mutex and stalling operations
by other devices that use the tty mutex.
A review of n_hdlc read and write code shows:
1. neither BKL or tty mutex are required for correct operation
2. read can block while read data is available if data is posted
between availability check and call to interruptible_sleep_on()
3. write does not set process state to TASK_INTERRUPTIBLE
on each pass through the processing loop which can cause
unneeded scheduling of the thread
The unnecessary tty mutex references have been removed.
Read changed to use same code as n_tty read
for completing reads and blocking.
Write corrected to set process state to TASK_INTERRUPTIBLE on each pass
through processing loop.
Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/tty/n_hdlc.c | 90 +++++++++++++++++++++++++-------------------------
1 files changed, 45 insertions(+), 45 deletions(-)
diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index 47d3228..52fc0c9 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -581,8 +581,9 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
__u8 __user *buf, size_t nr)
{
struct n_hdlc *n_hdlc = tty2n_hdlc(tty);
- int ret;
+ int ret = 0;
struct n_hdlc_buf *rbuf;
+ DECLARE_WAITQUEUE(wait, current);
if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_tty_read() called\n",__FILE__,__LINE__);
@@ -598,57 +599,55 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
return -EFAULT;
}
- tty_lock();
+ add_wait_queue(&tty->read_wait, &wait);
for (;;) {
if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
- tty_unlock();
- return -EIO;
+ ret = -EIO;
+ break;
}
+ if (tty_hung_up_p(file))
+ break;
- n_hdlc = tty2n_hdlc (tty);
- if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC ||
- tty != n_hdlc->tty) {
- tty_unlock();
- return 0;
- }
+ set_current_state(TASK_INTERRUPTIBLE);
rbuf = n_hdlc_buf_get(&n_hdlc->rx_buf_list);
- if (rbuf)
+ if (rbuf) {
+ if (rbuf->count > nr) {
+ /* too large for caller's buffer */
+ ret = -EOVERFLOW;
+ } else {
+ if (copy_to_user(buf, rbuf->buf, rbuf->count))
+ ret = -EFAULT;
+ else
+ ret = rbuf->count;
+ }
+
+ if (n_hdlc->rx_free_buf_list.count >
+ DEFAULT_RX_BUF_COUNT)
+ kfree(rbuf);
+ else
+ n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, rbuf);
break;
+ }
/* no data */
if (file->f_flags & O_NONBLOCK) {
- tty_unlock();
- return -EAGAIN;
+ ret = -EAGAIN;
+ break;
}
-
- interruptible_sleep_on (&tty->read_wait);
+
+ schedule();
+
if (signal_pending(current)) {
- tty_unlock();
- return -EINTR;
+ ret = -EINTR;
+ break;
}
}
-
- if (rbuf->count > nr)
- /* frame too large for caller's buffer (discard frame) */
- ret = -EOVERFLOW;
- else {
- /* Copy the data to the caller's buffer */
- if (copy_to_user(buf, rbuf->buf, rbuf->count))
- ret = -EFAULT;
- else
- ret = rbuf->count;
- }
-
- /* return HDLC buffer to free list unless the free list */
- /* count has exceeded the default value, in which case the */
- /* buffer is freed back to the OS to conserve memory */
- if (n_hdlc->rx_free_buf_list.count > DEFAULT_RX_BUF_COUNT)
- kfree(rbuf);
- else
- n_hdlc_buf_put(&n_hdlc->rx_free_buf_list,rbuf);
- tty_unlock();
+
+ remove_wait_queue(&tty->read_wait, &wait);
+ __set_current_state(TASK_RUNNING);
+
return ret;
} /* end of n_hdlc_tty_read() */
@@ -691,14 +690,15 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
count = maxframe;
}
- tty_lock();
-
add_wait_queue(&tty->write_wait, &wait);
- set_current_state(TASK_INTERRUPTIBLE);
+
+ for (;;) {
+ set_current_state(TASK_INTERRUPTIBLE);
- /* Allocate transmit buffer */
- /* sleep until transmit buffer available */
- while (!(tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list))) {
+ tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list);
+ if (tbuf)
+ break;
+
if (file->f_flags & O_NONBLOCK) {
error = -EAGAIN;
break;
@@ -719,7 +719,7 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
}
}
- set_current_state(TASK_RUNNING);
+ __set_current_state(TASK_RUNNING);
remove_wait_queue(&tty->write_wait, &wait);
if (!error) {
@@ -731,7 +731,7 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
n_hdlc_buf_put(&n_hdlc->tx_buf_list,tbuf);
n_hdlc_send_frames(n_hdlc,tty);
}
- tty_unlock();
+
return error;
} /* end of n_hdlc_tty_write() */
--
1.7.1
^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH 5/5] tty/serial: fix apbuart build
2011-01-31 16:28 [GIT PATCH] TTY/serial driver fixes for .38 Greg KH
` (3 preceding siblings ...)
2011-01-31 16:31 ` [PATCH 4/5] n_hdlc: fix read and write locking Greg Kroah-Hartman
@ 2011-01-31 16:31 ` Greg Kroah-Hartman
4 siblings, 0 replies; 8+ messages in thread
From: Greg Kroah-Hartman @ 2011-01-31 16:31 UTC (permalink / raw)
To: linux-kernel
Cc: Randy Dunlap, Daniel Hellstrom, Andrew Morton, Greg Kroah-Hartman
From: Randy Dunlap <randy.dunlap@oracle.com>
Fix build errors by selecting SERIAL_CORE:
ERROR: "uart_register_driver" [drivers/tty/serial/apbuart.ko] undefined!
ERROR: "uart_write_wakeup" [drivers/tty/serial/apbuart.ko] undefined!
ERROR: "uart_update_timeout" [drivers/tty/serial/apbuart.ko] undefined!
ERROR: "uart_get_divisor" [drivers/tty/serial/apbuart.ko] undefined!
ERROR: "uart_get_baud_rate" [drivers/tty/serial/apbuart.ko] undefined!
ERROR: "uart_add_one_port" [drivers/tty/serial/apbuart.ko] undefined!
ERROR: "uart_unregister_driver" [drivers/tty/serial/apbuart.ko] undefined!
ERROR: "uart_remove_one_port" [drivers/tty/serial/apbuart.ko] undefined!
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/tty/serial/Kconfig | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index b1682d7..2b83346 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1518,6 +1518,7 @@ config SERIAL_BCM63XX_CONSOLE
config SERIAL_GRLIB_GAISLER_APBUART
tristate "GRLIB APBUART serial support"
depends on OF
+ select SERIAL_CORE
---help---
Add support for the GRLIB APBUART serial port.
--
1.7.1
^ permalink raw reply [flat|nested] 8+ messages in thread