commit 6befa9d883 upstream.
Do not probe all serial drivers by of_serial.c which are using
device_type = "serial"; property. Only drivers which have valid
compatible strings listed in the driver should be probed.
When PORT_UNKNOWN is setup probe will fail anyway.
Arnd quotation about driver historical background:
"when I wrote that driver initially, the idea was that it would
get used as a stub to hook up all other serial drivers but after
that, the common code learned to create platform devices from DT"
This patch fix the problem with on the system with xilinx_uartps and
16550a where of_serial failed to register for xilinx_uartps and because
of irq_dispose_mapping() removed irq_desc. Then when xilinx_uartps was asking
for irq with request_irq() EINVAL is returned.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7fd6f640f2 upstream.
Trying to write console output from within the serial console driver
while the port->lock is held causes recursive deadlock:
CPU 0
spin_lock_irqsave(&port->lock)
printk()
console_unlock()
call_console_drivers()
serial8250_console_write()
spin_lock_irqsave(&port->lock)
** DEADLOCK **
The 8250_dw i/o accessors try to write a console error message if the
LCR workaround was unsuccessful. When the port->lock is already held
(eg., when called from serial8250_set_termios()), this deadlocks.
Make the error message a FIXME until a general solution is devised.
Cc: Tim Kryger <tim.kryger@gmail.com>
Reported-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f2e0ea8611 upstream.
I'm still receiving reports to my email address, so let's point this
at the linux-serial mailing list instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f0bf0bd079 upstream.
This problem was taken care of three times already in
* b0de59b573 (TTY: do not update
atime/mtime on read/write),
* 37b7f3c765 (TTY: fix atime/mtime
regression), and
* b0b885657b (tty: fix up atime/mtime
mess, take three)
But it still misses one point. As John Paul correctly points out, we
do not care about setting date. If somebody ever changes wall
time backwards (by mistake for example), tty timestamps are never
updated until the original wall time passes.
So check the absolute difference of times and if it large than "8
seconds or so", always update the time. That means we will update
immediatelly when changing time. Ergo, CAP_SYS_TIME can foul the
check, but it was always that way.
Thanks John for serving me this so nicely debugged.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: John Paul Perry <john_paul.perry@alcatel-lucent.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 79fbf4a550 upstream.
Fix overflow bug in tty_wait_until_sent on 64-bit machines, where an
infinite timeout (0) would be passed to the underlying tty-driver's
wait_until_sent-operation as a negative timeout (-1), causing it to
return immediately.
This manifests itself for example as tcdrain() returning immediately,
drivers not honouring the drain flags when setting terminal attributes,
or even dropped data on close as a requested infinite closing-wait
timeout would be ignored.
The first symptom was reported by Asier LLANO who noted that tcdrain()
returned prematurely when using the ftdi_sio usb-serial driver.
Fix this by passing 0 rather than MAX_SCHEDULE_TIMEOUT (LONG_MAX) to the
underlying tty driver.
Note that the serial-core wait_until_sent-implementation is not affected
by this bug due to a lucky chance (comparison to an unsigned maximum
timeout), and neither is the cyclades one that had an explicit check for
negative timeouts, but all other tty drivers appear to be affected.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: ZIV-Asier Llano Palacios <asier.llano@cgglobal.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 19e3ae6b4f upstream.
The vcs device's poll/fasync support relies on the vt notifier to signal
changes to the screen content. Notifier invocations were missing for
changes that comes through the selection interface though. Fix that.
Tested with BRLTTY 5.2.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Cc: Dave Mielke <dave@mielke.cc>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 37480a0568 upstream.
Commit 26df6d1340 ("tty: Add EXTPROC support for LINEMODE")
allows a process which has opened a pty master to send _any_ signal
to the process group of the pty slave. Although potentially
exploitable by a malicious program running a setuid program on
a pty slave, it's unknown if this exploit currently exists.
Limit to signals actually used.
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Howard Chu <hyc@symas.com>
Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1ff383a4c3 upstream.
This patch adds waiting until transmit buffer and shifter will be empty
before clock disabling.
Without this fix it's possible to have clock disabled while data was
not transmited yet, which causes unproper state of TX line and problems
in following data transfers.
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 37b1645788 upstream.
Kernel oops can cause the tty to be unreleaseable (for example, if
n_tty_read() crashes while on the read_wait queue). This will cause
tty_release() to endlessly loop without sleeping.
Use a killable sleep timeout which grows by 2n+1 jiffies over the interval
[0, 120 secs.) and then jumps to forever (but still killable).
NB: killable just allows for the task to be rewoken manually, not
to be terminated.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 547039ec50 upstream.
uart_get_baud_rate() will return baud == 0 if the max rate is set
to the "magic" 38400 rate and the SPD_* flags are also specified.
On the first iteration, if the current baud rate is higher than the
max, the baud rate is clamped at the max (which in the degenerate
case is 38400). On the second iteration, the now-"magic" 38400 baud
rate selects the possibly higher alternate baud rate indicated by
the SPD_* flag. Since only two loop iterations are performed, the
loop is exited, a kernel WARNING is generated and a baud rate of
0 is returned.
Reproducible with:
setserial /dev/ttyS0 spd_hi base_baud 38400
Only perform the "magic" 38400 -> SPD_* baud transform on the first
loop iteration, which prevents the degenerate case from recognizing
the clamped baud rate as the "magic" 38400 value.
Reported-by: Robert Święcki <robert@swiecki.net>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ae84db9661 upstream.
When a tty is opened for the serial console, the termios c_cflag
settings are inherited from the console line settings.
However, if the tty is subsequently closed, the termios settings
are lost. This results in a garbled console if the console is later
suspended and resumed.
Preserve the termios c_cflag for the serial console when the tty
is shutdown; this reflects the most recent line settings.
Fixes: Bugzilla #69751, 'serial console does not wake from S3'
Reported-by: Valerio Vanni <valerio.vanni@inwind.it>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fe418231b1 ]
Fix detection of BREAK on sunsab serial console: BREAK detection was only
performed when there were also serial characters received simultaneously.
To handle all BREAKs correctly, the check for BREAK and the corresponding
call to uart_handle_break() must also be done if count == 0, therefore
duplicate this code fragment and pull it out of the loop over the received
characters.
Patch applies to 3.16-rc6.
Signed-off-by: Christopher Alexander Tobias Schulze <cat.schulze@alice-dsl.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c49436b657 upstream.
When configured with UART_16550_COMPATIBLE=NO or in versions prior to
the introduction of this option, the Designware UART will ignore writes
to the LCR if the UART is busy. The current workaround saves a copy of
the last written LCR and re-writes it in the ISR for a special interrupt
that is raised when a write was ignored.
Unfortunately, interrupts are typically disabled prior to performing a
sequence of register writes that include the LCR so the point at which
the retry occurs is too late. An example is serial8250_do_set_termios()
where an ignored LCR write results in the baud divisor not being set and
instead a garbage character is sent out the transmitter.
Furthermore, since serial_port_out() offers no way to indicate failure,
a serious effort must be made to ensure that the LCR is actually updated
before returning back to the caller. This is difficult, however, as a
UART that was busy during the first attempt is likely to still be busy
when a subsequent attempt is made unless some extra action is taken.
This updated workaround reads back the LCR after each write to confirm
that the new value was accepted by the hardware. Should the hardware
ignore a write, the TX/RX FIFOs are cleared and the receive buffer read
before attempting to rewrite the LCR out of the hope that doing so will
force the UART into an idle state. While this may seem unnecessarily
aggressive, writes to the LCR are used to change the baud rate, parity,
stop bit, or data length so the data that may be lost is likely not
important. Admittedly, this is far from ideal but it seems to be the
best that can be done given the hardware limitations.
Lastly, the revised workaround doesn't touch the LCR in the ISR, so it
avoids the possibility of a "serial8250: too much work for irq" lock up.
This problem is rare in real situations but can be reproduced easily by
wiring up two UARTs and running the following commands.
# stty -F /dev/ttyS1 echo
# stty -F /dev/ttyS2 echo
# cat /dev/ttyS1 &
[1] 375
# echo asdf > /dev/ttyS1
asdf
[ 27.700000] serial8250: too much work for irq96
[ 27.700000] serial8250: too much work for irq96
[ 27.710000] serial8250: too much work for irq96
[ 27.710000] serial8250: too much work for irq96
[ 27.720000] serial8250: too much work for irq96
[ 27.720000] serial8250: too much work for irq96
[ 27.730000] serial8250: too much work for irq96
[ 27.730000] serial8250: too much work for irq96
[ 27.740000] serial8250: too much work for irq96
Signed-off-by: Tim Kryger <tim.kryger@linaro.org>
Reviewed-by: Matt Porter <matt.porter@linaro.org>
Reviewed-by: Markus Mayer <markus.mayer@linaro.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
[wangnan: backport to 3.10.43:
- adjust context
- remove unneeded local var]
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 33acbb8269 upstream.
When a serial port is configured for RTS/CTS flow control, serial core
will disable the transmitter if it observes CTS is de-asserted. This is
perfectly reasonable and appropriate when the UART lacks the ability to
automatically perform CTS flow control.
However, if the UART hardware can manage flow control automatically, it
is important that software not get involved. When the DesignWare UART
enables 16C750 style auto-RTS/CTS it stops generating interrupts for
changes in CTS state so software mostly stays out of the way. However,
it does report the true state of CTS in the MSR so software may notice
it is de-asserted and respond by improperly disabling the transmitter.
Once this happens the transmitter will be blocked forever.
To avoid this situation, we simply lie to the 8250 and serial core by
reporting that CTS is asserted whenever auto-RTS/CTS mode is enabled.
Signed-off-by: Tim Kryger <tim.kryger@linaro.org>
Reviewed-by: Matt Porter <matt.porter@linaro.org>
Reviewed-by: Markus Mayer <markus.mayer@linaro.org>
Cc: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f8fd1b0350 upstream.
__dma_tx_complete is not protected against concurrent
call of serial8250_tx_dma. it can lead to circular tail
index corruption or parallel call of serial_tx_dma on the
same data portion.
This patch fixes this issue by holding the port lock.
Signed-off-by: Loic Poulain <loic.poulain@intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4291086b1f upstream.
The tty atomic_write_lock does not provide an exclusion guarantee for
the tty driver if the termios settings are LECHO & !OPOST. And since
it is unexpected and not allowed to call TTY buffer helpers like
tty_insert_flip_string concurrently, this may lead to crashes when
concurrect writers call pty_write. In that case the following two
writers:
* the ECHOing from a workqueue and
* pty_write from the process
race and can overflow the corresponding TTY buffer like follows.
If we look into tty_insert_flip_string_fixed_flag, there is:
int space = __tty_buffer_request_room(port, goal, flags);
struct tty_buffer *tb = port->buf.tail;
...
memcpy(char_buf_ptr(tb, tb->used), chars, space);
...
tb->used += space;
so the race of the two can result in something like this:
A B
__tty_buffer_request_room
__tty_buffer_request_room
memcpy(buf(tb->used), ...)
tb->used += space;
memcpy(buf(tb->used), ...) ->BOOM
B's memcpy is past the tty_buffer due to the previous A's tb->used
increment.
Since the N_TTY line discipline input processing can output
concurrently with a tty write, obtain the N_TTY ldisc output_lock to
serialize echo output with normal tty writes. This ensures the tty
buffer helper tty_insert_flip_string is not called concurrently and
everything is fine.
Note that this is nicely reproducible by an ordinary user using
forkpty and some setup around that (raw termios + ECHO). And it is
present in kernels at least after commit
d945cb9cce (pty: Rework the pty layer to
use the normal buffering logic) in 2.6.31-rc3.
js: add more info to the commit log
js: switch to bool
js: lock unconditionally
js: lock only the tty->ops->write call
References: CVE-2014-0196
Reported-and-tested-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b790f210fe upstream.
The sleep function was updated to put the serial port to sleep only when necessary.
This appears to resolve the errant behavior of the driver as described in
Kernel Bug 61961 – "My Exar Corp. XR17C/D152 Dual PCI UART modem does not
work with 3.8.0".
Signed-off-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 501fed45b7 upstream.
When 'console=hvc0' is specified to the kernel parameter in x86 KVM guest,
hvc console is setup within a kthread. However, that will cause SEGV
and the boot will fail when the driver is builtin to the kernel,
because currently hvc_console_setup() is annotated with '__init'. This
patch removes '__init' to boot the guest successfully with 'console=hvc0'.
Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@hds.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f76a1cbed1 upstream.
Commit 3e6c6f630a ("Delay creation of
khcvd thread") moved the call of hvc_init from being a device_initcall
into hvc_alloc, and used a non-null hvc_driver as indication of whether
hvc_init had already been called.
The problem with this is that hvc_driver is only assigned a value
at the bottom of hvc_init, and so there is a window where multiple
hvc_alloc calls can be in progress at the same time and hence try
and call hvc_init multiple times. Previously the use of device_init
guaranteed that hvc_init was only called once.
This manifests itself as sporadic instances of two hvc_init calls
racing each other, and with the loser of the race getting -EBUSY
from tty_register_driver() and hence that virtual console fails:
Couldn't register hvc console driver
virtio-ports vport0p1: error -16 allocating hvc for port
Here we add an atomic_t to guarantee we'll never run hvc_init twice.
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: 3e6c6f630a ("Delay creation of khcvd thread")
Reported-by: Jim Somerville <Jim.Somerville@windriver.com>
Tested-by: Jim Somerville <Jim.Somerville@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 723abd87f6 upstream.
The 'active' sysfs attribute should refer to the currently active tty
devices the console is running on, not the currently active console. The
console structure doesn't refer to any device in sysfs, only the tty the
console is running on has. So we need to print out the tty names in
'active', not the console names.
There is one special-case, which is tty0. If the console is directed to
it, we want 'tty0' to show up in the file, so user-space knows that the
messages get forwarded to the active VT. The ->device() callback would
resolve tty0, though. Hence, treat it special and don't call into the VT
layer to resolve it (plymouth is known to depend on it).
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Werner Fink <werner@suse.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0930b0950a upstream.
\E[3J console code (secure clear screen) needs to update_screen(vc)
in order to write-through blanks into off-screen video memory.
This has been removed accidentally in 3.6 by:
commit 81732c3b2f
Author: Jean-François Moine <moinejf@free.fr>
Date: Thu Sep 6 19:24:13 2012 +0200
tty vt: Fix line garbage in virtual console on command line edition
Signed-off-by: Petr Písař <petr.pisar@atlas.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3ac06b9056 upstream.
3GPP TS 07.10 states in section 5.4.6.3.7:
"The length byte contains the value 2 or 3 ... depending on the break
signal." The break byte is optional and if it is sent, the length is
3. In fact the driver was not able to work with modems that send this
break byte in their modem status control message. If the modem just
sends the break byte if it is really set, then weird things might
happen.
The code for deconding the modem status to the internal linux
presentation in gsm_process_modem has already a big comment about
this 2 or 3 byte length thing and it is already able to decode the
brk, but the code calling the gsm_process_modem function in
gsm_control_modem does not encode it and hand it over the right way.
This patch fixes this.
Without this fix if the modem sends the brk byte in it's modem status
control message the driver will hang when opening a muxed channel.
Signed-off-by: Lars Poeschel <poeschel@lemonage.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3685f19e07 upstream.
Tegra chips have 4 or 5 identical UART modules embedded. UARTs C..E have
their MODEM-control signals tied off to a static state. However UARTs A
and B can optionally route those signals to/from package pins, depending
on the exact pinmux configuration.
When these signals are not routed to package pins, false interrupts may
trigger either temporarily, or permanently, all while not showing up in
the IIR; it will read as NO_INT. This will eventually lead to the UART
IRQ being disabled due to unhandled interrupts. When this happens, the
kernel may print e.g.:
irq 68: nobody cared (try booting with the "irqpoll" option)
In order to prevent this, enable UART_BUG_NOMSR. This prevents
UART_IER_MSI from being enabled, which prevents the false interrupts
from triggering.
In practice, this is not needed under any of the following conditions:
* On Tegra chips after Tegra30, since the HW bug has apparently been
fixed.
* On UARTs C..E since their MODEM control signals are tied to the correct
static state which doesn't trigger the issue.
* On UARTs A..B if the MODEM control signals are routed out to package
pins, since they will then carry valid signals.
However, we ignore these exceptions for now, since they are only relevant
if a board actually hooks up more than a 4-wire UART, and no currently
supported board does this. If we ever support a board that does, we can
refine the algorithm that enables UART_BUG_NOMSR to take those exceptions
into account, and/or read a flag from DT/... that indicates that the
board has hooked up and pinmux'd more than a 4-wire UART.
Reported-by: Olof Johansson <olof@lixom.net> # autotester
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9c5320f8d7 upstream.
Fix the initialisation of older Quatech serial cards which are fitted with
the AMCC PCI Matchmaker interface chip.
Signed-off-by: Jonathan Woithe (jwoithe@just42.net)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0cc7c6c791 upstream.
Interrupts were being cleaned up late in the shutdown handler, it is possible
that an interrupt can occur and schedule a tasklet that runs after the port is
cleaned up. There is a null dereference due to this race condition with the
following stacktrace:
[<c02092b0>] (atmel_tasklet_func+0x514/0x814) from [<c001fd34>] (tasklet_action+0x70/0xa8)
[<c001fd34>] (tasklet_action+0x70/0xa8) from [<c001f60c>] (__do_softirq+0x90/0x144)
[<c001f60c>] (__do_softirq+0x90/0x144) from [<c001fa18>] (irq_exit+0x40/0x4c)
[<c001fa18>] (irq_exit+0x40/0x4c) from [<c000e298>] (handle_IRQ+0x64/0x84)
[<c000e298>] (handle_IRQ+0x64/0x84) from [<c000d6c0>] (__irq_svc+0x40/0x50)
[<c000d6c0>] (__irq_svc+0x40/0x50) from [<c0208060>] (atmel_rx_dma_release+0x88/0xb8)
[<c0208060>] (atmel_rx_dma_release+0x88/0xb8) from [<c0209740>] (atmel_shutdown+0x104/0x160)
[<c0209740>] (atmel_shutdown+0x104/0x160) from [<c0205e8c>] (uart_port_shutdown+0x2c/0x38)
Signed-off-by: Marek Roszko <mark.roszko@gmail.com>
Acked-by: Leilei Zhao <leilei.zhao@atmel.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fe43390702 upstream.
When the pl011 is being used for a console, pl011_console_write forces
the control register (CR) to enable the UART for transmission and then
restores this to the original value afterwards. It does this while
holding the port lock.
Unfortunately, when the uart is started or shutdown - say in response to
userland using the serial device for a terminal - then this updates the
control register without any locking.
This means we can have
pl011_console_write Save CR
pl011_startup Initialise CR, e.g. enable receive
pl011_console_write Restore old CR with receive not enabled
this result is a serial port which doesn't respond to any input.
A similar race in reverse could happen when the device is shutdown.
We can fix these problems by taking the port lock when updating CR.
Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d24c195f90 upstream.
Newer Intel PCHs with LPSS have the same Designware controllers than
Haswell but ACPI IDs are different. Add these IDs to the driver list.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dc1dc2f8a5 upstream.
When booting a multi-platform m68k kernel on a non-Mac with "console=ttyS0"
on the kernel command line, it crashes with:
Unable to handle kernel NULL pointer dereference at virtual address (null)
Oops: 00000000
PC: [<0013ad28>] __pmz_startup+0x32/0x2a0
...
Call Trace: [<002c5d3e>] pmz_console_setup+0x64/0xe4
The normal tty driver doesn't crash, because init_pmz() checks
pmz_ports_count again after calling pmz_probe().
In the serial console initialization path, pmz_console_init() doesn't do
this, causing the driver to crash later.
Add a check for pmz_ports_count to fix this.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d969de8d83 upstream.
Due to missing braces on an if statement, in presence of a device_node a
port was always assigned -1, regardless of any alias entries in the
device tree. Conversely, if device_node was NULL, an unitialized port
ended up being used.
This patch adds the missing braces, fixing the issues.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a9fbf4d591 upstream.
Commit d0380e6c3c (early_printk:
consolidate random copies of identical code) added in 3.10 introduced
a check for con->index == -1 in early_console_register().
Initialize index to -1 for the xenboot console so earlyprintk=xen
works again.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 19b85cfb19 upstream.
Fix tty_kref leak when tty_buffer_request room fails in dma-rx path.
Note that the tty ref isn't really needed anymore, but as the leak has
always been there, fixing it before removing should makes it easier to
backport the fix.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fc0919c68c upstream.
Fix tty-kref leak introduced by commit 384e301e ("pch_uart: fix a
deadlock when pch_uart as console") which never put its tty reference.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5cec7bf699 upstream.
Commit 'e7f3880cd9b98c5bf9391ae7acdec82b75403776'
tty: Fix recursive deadlock in tty_perform_flush()
introduced a regression where tcflush() does not generate
SIGTTOU for background process groups.
Make sure ioctl(TCFLSH) calls tty_check_change() when
invoked from the line discipline.
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 03e1261778 upstream.
Starting from v3.10 (probably commit f91e259041: "tty: Signal
foreground group processes in hangup") disassociate_ctty() sends SIGCONT
if tty && on_exit. This breaks LSB test-suite, in particular test8 in
_exit.c and test40 in sigcon5.c.
Put the "!on_exit" check back to restore the old behaviour.
Review by Peter Hurley:
"Yes, this regression was introduced by me in that commit. The effect
of the regression is that ptys will receive a SIGCONT when, in similar
circumstances, ttys would not.
The fact that two test vectors accidentally tripped over this
regression suggests that some other apps may as well.
Thanks for catching this"
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Karel Srot <ksrot@redhat.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d220980b70 upstream.
This solves a problem observed in kexec'ed kernel where 200ms timeout is
too short and bootconsole fails to initialize. Console did eventually
become workable but much later into the boot process.
Observed timeout was around 260ms, but I decided to make it a little bigger
for more reliability.
This has been tested on Power7 machine with Petitboot as a primary
bootloader and PowerNV firmware.
Signed-off-by: Eugene Surovegin <surovegin@google.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 079a036f42 upstream.
Without this patch the driver waits ~1 ms for the UART to become idle. At
115200n8 this time is (theoretically) enough to transfer 11.5 characters
(= 115200 bits/s / (10 Bits/char) * 1ms). As the mxs-auart has a fifo size
of 16 characters the clock is gated too early. The problem is worse for
lower baud rates.
This only happens to really shut down the transmitter in the middle of a
transfer if /dev/ttyAPPx isn't opened in userspace (e.g. by a getty) but
was at least once (because the bootloader doesn't disable the transmitter).
So increase the timeout to 20 ms which should be enough for 9600n8, too.
Moreover skip gating the clock if the timeout is elapsed.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d5a12ea7a9 upstream.
Platform drivers use "platform:" prefix in module alias.
Also use DRIVER_NAME in MODULE_ALIAS to make module autoloading work.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d970d7fe65 upstream.
The handler needs to ack the pending events before actually handling them.
Otherwise a new event might come in after it it considered non-pending or
handled and is acked then without being handled. So this event is only
noticed when the next interrupt happens.
Without this patch an i.MX28 based machine running an rt-patched kernel
regularly hangs during boot.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dd5e6d6a3d upstream.
We can't use dev->mod_index for selecting the interrupt routing entry,
because it's not an index into interrupt routing table. It will be even
wrong on a machine with 2 CPUs (4 cores). But all needed information is
contained in the PAT entries for the serial ports. mod[0] contains the
iosapic address and mod_info has some indications for the interrupt
input (at least it looks like it). This patch implements the searching
for the right iosapic and uses this interrupt input information.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1d9e689c93 upstream.
The function tty_port_tty_hangup() could leak a reference to the tty_struct:
struct tty_struct *tty = tty_port_tty_get(port);
if (tty && (!check_clocal || !C_CLOCAL(tty))) {
tty_hangup(tty);
tty_kref_put(tty);
}
If tty != NULL and the second condition is false we never call tty_kref_put and
the reference is leaked.
Fix by always calling tty_kref_put() which accepts a NULL argument.
The patch fixes a regression introduced by commit aa27a094.
Acked-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Gianluca Anzolin <gianluca@sottospazio.it>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 64e377dcd7 upstream.
Commit 19ffd68f81
('pty: Remove redundant itty reset') introduced a regression
whereby the other pty's linkage is not cleared on teardown.
This triggers a false positive diagnostic in testing.
Properly reset the itty linkage.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pul tty fixes from Greg Kroah-Hartman:
"Here are two tty core fixes that resolve some regressions that have
been reported recently. Both tiny fixes, but needed"
* tag 'tty-3.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: Fix transient pty write() EIO
tty/vt: Return EBUSY if deallocating VT1 and it is busy
