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2017-05-24serial: meson: hide an unused functionArnd Bergmann
The newly added meson_uart_enable_tx_engine function is only called from the console setup, not the runtime uart, which has an open-coded version of the same register access. This produces a harmless warning when the console code is disabled: drivers/tty/serial/meson_uart.c:127:13: error: 'meson_uart_enable_tx_engine' defined but not used [-Werror=unused-function] Let's move the function inside of the #ifdef to avoid the warning. Fixes: ba50f1df13c8 ("serial: meson: remove unneeded variable assignment in meson_serial_port_write") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: enable serdev supportJohan Hovold
Enable serdev support by using the new device-registration helpers. Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18tty/serdev: add serdev registration interfaceJohan Hovold
Add a new interface for registering a serdev controller and clients, and a helper function to deregister serdev devices (or a tty device) that were previously registered using the new interface. Once every driver currently using the tty_port_register_device() helpers have been vetted and converted to use the new serdev registration interface (at least for deregistration), we can move serdev registration to the current helpers and get rid of the serdev-specific functions. Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serdev: Restore serdev_device_write_buf for atomic contextStefan Wahren
Starting with commit 6fe729c4bdae ("serdev: Add serdev_device_write subroutine") the function serdev_device_write_buf cannot be used in atomic context anymore (mutex_lock is sleeping). So restore the old behavior. Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Fixes: 6fe729c4bdae ("serdev: Add serdev_device_write subroutine") Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: core: fix crash in uart_suspend_portLucas Stach
With serdev we might end up with serial ports that have no cdev exported to userspace, as they are used as the bus interface to other devices. In that case serial_match_port() won't be able to find a matching tty_dev. Skip the irq wakeup enabling in that case, as serdev will make sure to keep the port active, as long as there are devices depending on it. Fixes: 8ee3fde04758 (tty_port: register tty ports with serdev bus) Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18tty: fix port buffer lockingVegard Nossum
tty_insert_flip_string_fixed_flag() is racy against itself when called from the ioctl(TCXONC, TCION/TCIOFF) path [1] and the flush_to_ldisc() workqueue path [2]. The problem is that port->buf.tail->used is modified without consistent locking; the ioctl path takes tty->atomic_write_lock, whereas the workqueue path takes ldata->output_lock. We cannot simply take ldata->output_lock, since that is specific to the N_TTY line discipline. It might seem natural to try to take port->buf.lock inside tty_insert_flip_string_fixed_flag() and friends (where port->buf is actually used/modified), but this creates problems for flush_to_ldisc() which takes it before grabbing tty->ldisc_sem, o_tty->termios_rwsem, and ldata->output_lock. Therefore, the simplest solution for now seems to be to take tty->atomic_write_lock inside tty_port_default_receive_buf(). This lock is also used in the write path [3] with a consistent ordering. [1]: Call Trace: tty_insert_flip_string_fixed_flag pty_write tty_send_xchar // down_read(&o_tty->termios_rwsem) // mutex_lock(&tty->atomic_write_lock) n_tty_ioctl_helper n_tty_ioctl tty_ioctl // down_read(&tty->ldisc_sem) do_vfs_ioctl SyS_ioctl [2]: Workqueue: events_unbound flush_to_ldisc Call Trace: tty_insert_flip_string_fixed_flag pty_write tty_put_char __process_echoes commit_echoes // mutex_lock(&ldata->output_lock) n_tty_receive_buf_common n_tty_receive_buf2 tty_ldisc_receive_buf // down_read(&o_tty->termios_rwsem) tty_port_default_receive_buf // down_read(&tty->ldisc_sem) flush_to_ldisc // mutex_lock(&port->buf.lock) process_one_work [3]: Call Trace: tty_insert_flip_string_fixed_flag pty_write n_tty_write // mutex_lock(&ldata->output_lock) // down_read(&tty->termios_rwsem) do_tty_write (inline) // mutex_lock(&tty->atomic_write_lock) tty_write // down_read(&tty->ldisc_sem) __vfs_write vfs_write SyS_write The bug can result in about a dozen different crashes depending on what exactly gets corrupted when port->buf.tail->used points outside the buffer. The patch passes my LOCKDEP/PROVE_LOCKING testing but more testing is always welcome. Found using syzkaller. Cc: <stable@vger.kernel.org> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18tty: ehv_bytechan: clean up init error handlingJohan Hovold
Straighten out the initcall error handling to avoid deregistering a never-registered tty driver (something which would lead to a NULL-pointer dereference) in the most unlikely event that driver registration fails (e.g. we've run out of major numbers). Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: ifx6x60: fix use-after-free on module unloadJohan Hovold
Make sure to deregister the SPI driver before releasing the tty driver to avoid use-after-free in the SPI remove callback where the tty devices are deregistered. Fixes: 72d4724ea54c ("serial: ifx6x60: Add modem power off function in the platform reboot process") Cc: stable <stable@vger.kernel.org> # 3.8 Cc: Jun Chen <jun.d.chen@intel.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: altera_jtaguart: adding iounmap()Alexey Khoroshilov
The driver does ioremap(port->mapbase, ALTERA_JTAGUART_SIZE), but there is no any iounmap(). Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Acked-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: exar: Fix stuck MSIsJan Kiszka
After migrating 8250_exar to MSI in 172c33cb61da, we can get stuck without further interrupts because of the special wake-up event these chips send. They are only cleared by reading INT0. As we fail to do so during startup and shutdown, we can leave the interrupt line asserted, which is fatal with edge-triggered MSIs. Add the required reading of INT0 to startup and shutdown. Also account for the fact that a pending wake-up interrupt means we have to return 1 from exar_handle_irq. Drop the unneeded reading of INT1..3 along with this - those never reset anything. An alternative approach would have been disabling the wake-up interrupt. Unfortunately, this feature (REGB[17] = 1) is not available on the XR17D15X. Fixes: 172c33cb61da ("serial: exar: Enable MSI support") Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: efm32: Fix parity management in 'efm32_uart_console_get_options()'Christophe JAILLET
UARTn_FRAME_PARITY_ODD is 0x0300 UARTn_FRAME_PARITY_EVEN is 0x0200 So if the UART is configured for EVEN parity, it would be reported as ODD. Fix it by correctly testing if the 2 bits are set. Fixes: 3afbd89c9639 ("serial/efm32: add new driver") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serdev: fix tty-port client deregistrationJohan Hovold
The port client data must be set when registering the serdev controller or client deregistration will fail (and the serdev devices are left registered and allocated) if the port was never opened in between. Make sure to clear the port client data on any probe errors to avoid a use-after-free when the client is later deregistered unconditionally (e.g. in a tty-port deregistration helper). Also move port client operation initialisation to registration. Note that the client ops must be restored on failed probe. Fixes: bed35c6dfa6a ("serdev: add a tty port controller driver") Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Rob Herring <robh@kernel.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18Revert "tty_port: register tty ports with serdev bus"Johan Hovold
This reverts commit 8ee3fde047589dc9c201251f07d0ca1dc776feca. The new serdev bus hooked into the tty layer in tty_port_register_device() by registering a serdev controller instead of a tty device whenever a serdev client is present, and by deregistering the controller in the tty-port destructor. This is broken in several ways: Firstly, it leads to a NULL-pointer dereference whenever a tty driver later deregisters its devices as no corresponding character device will exist. Secondly, far from every tty driver uses tty-port refcounting (e.g. serial core) so the serdev devices might never be deregistered or deallocated. Thirdly, deregistering at tty-port destruction is too late as the underlying device and structures may be long gone by then. A port is not released before an open tty device is closed, something which a registered serdev client can prevent from ever happening. A driver callback while the device is gone typically also leads to crashes. Many tty drivers even keep their ports around until the driver is unloaded (e.g. serial core), something which even if a late callback never happens, leads to leaks if a device is unbound from its driver and is later rebound. The right solution here is to add a new tty_port_unregister_device() helper and to never call tty_device_unregister() whenever the port has been claimed by serdev, but since this requires modifying just about every tty driver (and multiple subsystems) it will need to be done incrementally. Reverting the offending patch is the first step in fixing the broken lifetime assumptions. A follow-up patch will add a new pair of tty-device registration helpers, which a vetted tty driver can use to support serdev (initially serial core). When every tty driver uses the serdev helpers (at least for deregistration), we can add serdev registration to tty_port_register_device() again. Note that this also fixes another issue with serdev, which currently allocates and registers a serdev controller for every tty device registered using tty_port_device_register() only to immediately deregister and deallocate it when the corresponding OF node or serdev child node is missing. This should be addressed before enabling serdev for hot-pluggable buses. Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Rob Herring <robh@kernel.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18drivers/tty: 8250: only call fintek_8250_probe when doing port I/OArd Biesheuvel
Commit fa01e2ca9f53 ("serial: 8250: Integrate Fintek into 8250_base") modified the probing logic for PNP0501 devices, to remove a collision between the generic 16550A driver and the Fintek driver, which reused the same ACPI _HID. The Fintek device probe is now incorporated into the common 8250 probe path, and gets called for all discovered 16550A compatible devices, including ones that are MMIO mapped rather than IO mapped. However, the Fintek driver assumes the port base is a I/O address, and proceeds to probe some arbitrary offsets above it. This is generally a wrong thing to do, but on ARM systems (having no native port I/O), this may result in faulting accesses of completely unrelated MMIO regions in the PCI I/O space. Given that this is at serial probe time, this results in hard to diagnose crashes at boot. So let's restrict the Fintek probe to devices that we know are using port I/O in the first place. Fixes: fa01e2ca9f53 ("serial: 8250: Integrate Fintek into 8250_base") Suggested-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Ricardo Ribalda <ricardo.ribalda@gmail.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: xilinx_uartps: Fix the error pathShubhrajyoti Datta
Fix the runtime calls in the error path. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: change interrupt description to tty nameHeiner Kallweit
Change interrupt description from driver name to tty name (e.g. ttyAML0). If multiple serial ports are enabled this allows to determine which interrupt belongs to which port in /proc/interrupts. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: remove use of flag UPF_IOREMAPHeiner Kallweit
Flag UPF_IOREMAP is used by the 8250 subsystem only, it's not used by the serial core. Therefore I don't see any benefit in using it here. In addition fix the order of calls in meson_uart_release_port. Unmapping needs to be done first, reversing call order in meson_uart_request_port. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: make use of uart_port member mapsizeHeiner Kallweit
Member mapsize of struct uart_port is meant to store the resource size. By using it we can get rid of meson_uart_res_size(). Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: remove dead code in meson_uart_change_speedHeiner Kallweit
val is set in both branches of the if clause, therefore the two removed lines are dead code. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: remove unneeded variable assignment in meson_serial_port_writeHeiner Kallweit
There's no need to set AML_UART_TX_EN in each call to meson_serial_port_write. In addition to meson_uart_startup set this flag in meson_serial_console_setup and meson_serial_early_console_setup. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: fix setting number of stop bitsHeiner Kallweit
The stop bit value as to be or'ed, so far this worked only just by chance because AML_UART_STOP_BIN_1SB is 0. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18tty/vt/keyboard: Remove AVR32 bits from the driverAndy Shevchenko
AVR32 is gone. Now it's time to clean up the driver by removing leftovers that was used by AVR32 related code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: pch_uart: use offset_in_page() macroGeliang Tang
Use offset_in_page() macro instead of open-coding. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18tty/serial: atmel: use offset_in_page() macroGeliang Tang
Use offset_in_page() macro instead of open-coding. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18drivers/tty/hvc: fix spelling mistake: "missmanaged" -> "mismanaged"Colin Ian King
Trivial fix to spelling mistake in printk message Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: exar: Preconfigure xr17v35x MPIOs as outputJan Kiszka
This is the safe default for GPIOs with unknown external wiring. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18imx-serial: RX DMA startup latencyPeter Senna Tschudin
18a4208 introduced a change to reduce the RX DMA latency on the first reception when the serial port was opened for reading. However it was claiming a hardirq unsafe lock after a hardirq safe lock which is not allowed and causes lockdep to complain verbosely. This patch changes the code to always start RX DMA earlier, instead of relying on the flags used to open the serial port removing the code that was looking for the serial file flags. Signed-off-by: Peter Senna Tschudin <peter.senna@collabora.com> Tested-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18tty: serdev-ttyport: return actual baudrate from ttyport_set_baudrateStefan Wahren
Instead of returning the requested baudrate, we better return the actual one because it isn't always the same. Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: sh-sci: Move uart_register_driver call to device probeSjoerd Simons
uart_register_driver call binds the driver to a specific device node through tty_register_driver call. This should typically happen during device probe call. In a multiplatform scenario, it is possible that multiple serial drivers are part of the kernel. Currently the driver registration fails if multiple serial drivers with overlapping major/minor numbers are included. Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: pl010: Move uart_register_driver call to device probeSjoerd Simons
uart_register_driver call binds the driver to a specific device node through tty_register_driver call. This should typically happen during device probe call. In a multiplatform scenario, it is possible that multiple serial drivers are part of the kernel. Currently the driver registration fails if multiple serial drivers with overlapping major/minor numbers are included. Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: sh-sci: Fix race condition causing garbage during shutdownGeert Uytterhoeven
If DMA is enabled and used, a burst of old data may be seen on the serial console during "poweroff" or "reboot". uart_flush_buffer() clears the circular buffer, but sci_port.tx_dma_len is not reset. This leads to a circular buffer overflow, dumping (UART_XMIT_SIZE - sci_port.tx_dma_len) bytes. To fix this, add a .flush_buffer() callback that resets sci_port.tx_dma_len. Inspired by commit 31ca2c63fdc0aee7 ("tty/serial: atmel: fix race condition (TX+DMA)"). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18drivers/serial: Add driver for Aspeed virtual UARTJeremy Kerr
This change adds a driver for the 16550-based Aspeed virtual UART device. We use a similar process to the of_serial driver for device probe, but expose some VUART-specific functions through sysfs too. The VUART is two UART 'front ends' connected by their FIFO (no actual serial line in between). One is on the BMC side (management controller) and one is on the host CPU side. This driver is for the BMC side. The sysfs files allow the BMC userspace, which owns the system configuration policy, to specify at what IO port and interrupt number the host side will appear to the host on the Host <-> BMC LPC bus. It could be different on a different system (though most of them use 3f8/4). OpenPOWER host firmware doesn't like it when the host-side of the VUART's FIFO is not drained. This driver only disables host TX discard mode when the port is in use. We set the VUART enabled bit when we bind to the device, and clear it on unbind. We don't want to do this on open/release, as the host may be using this bit to configure serial output modes, which is independent of whether the devices has been opened by BMC userspace. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: 8250: Add flag so drivers can avoid THRE probeJoel Stanley
The probing of THRE irq behaviour assumes the other end will be reading bytes out of the buffer in order to probe the port at driver init. In some cases the other end cannot be relied upon to read these bytes, so provide a flag for them to skip this step. Bit 19 was chosen as the flags are a int and the top bits are taken. Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: 8250_exar: Remove duplicate assignmentAndy Shevchenko
UPF_EXAR_EFR is set globally for each port enumerated by the driver. Thus, no need to repeat this in individual ->setup() hook. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: 8250: omap: Disable DMA for console UARTVignesh R
Kernel always writes log messages to console via serial8250_console_write()->serial8250_console_putchar() which directly accesses UART_TX register _without_ using DMA. But, if other processes like systemd using same UART port, then these writes are handled by a different code flow using 8250_omap driver where there is provision to use DMA. It seems that it is possible that both DMA and CPU might simultaneously put data to UART FIFO and lead to potential loss of data due to FIFO overflow and weird data corruption. This happens when both kernel console and userspace tries to write simultaneously to the same UART port. Therefore, disable DMA on kernel console port to avoid potential race between CPU and DMA. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-16staging: speakup: add tty-based comms functionsOkash Khawaja
This adds spk_ttyio.c file. It contains a set of functions which implement those methods in spk_synth struct which relate to sending bytes out using serial comms. Implementations in this file perform the same function but using TTY subsystem instead. Currently synths access serial ports, directly poking standard ISA ports by trying to steal them from serial driver. Some ISA cards actually need this way of doing it, but most other synthesizers don't, and can actually work by using the proper TTY subsystem through a new N_SPEAKUP line discipline. So this adds the methods for drivers to switch to accessing serial ports through the TTY subsystem, whenever appropriate. Signed-off-by: Okash Khawaja <okash.khawaja@gmail.com> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-16tty: export tty_open_by_driverOkash Khawaja
This exports tty_open_by_driver so that it can be called from other places inside the kernel. The checks for null file pointer are based on Alan Cox's patch here: http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1215095.html. Description below is quoted from it: "[RFC] tty_port: allow a port to be opened with a tty that has no file handle Let us create tty objects entirely in kernel space. Untested proposal to show why all the ideas around rewriting half the uart stack are not needed. With this a kernel created non file backed tty object could be used to handle data, and set terminal modes. Not all ldiscs can cope with this as N_TTY in particular has to work back to the fs/tty layer. The tty_port code is however otherwise clean of file handles as far as I can tell as is the low level tty port write path used by the ldisc, the configuration low level interfaces and most of the ldiscs. Currently you don't have any exposure to see tty hangups because those are built around the file layer. However a) it's a fixed port so you probably don't care about that b) if you do we can add a callback and c) you almost certainly don't want the userspace tear down/rebuild behaviour anyway. This should however be sufficient if we wanted for example to enumerate all the bluetooth bound fixed ports via ACPI and make them directly available. It doesn't deal with the case of a user opening a port that's also kernel opened and that would need some locking out (so it returned EBUSY if bound to a kernel device of some kind). That needs resolving along with how you "up" or "down" your new bluetooth device, or enumerate it while providing the existing tty API to avoid regressions (and to debug)." The exported funtion is used later in this patch set to gain access to tty_struct. [changed export symbol level - gkh] Signed-off-by: Okash Khawaja <okash.khawaja@gmail.com> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-10Merge tag 'hwparam-20170420' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull hw lockdown support from David Howells: "Annotation of module parameters that configure hardware resources including ioports, iomem addresses, irq lines and dma channels. This allows a future patch to prohibit the use of such module parameters to prevent that hardware from being abused to gain access to the running kernel image as part of locking the kernel down under UEFI secure boot conditions. Annotations are made by changing: module_param(n, t, p) module_param_named(n, v, t, p) module_param_array(n, t, m, p) to: module_param_hw(n, t, hwtype, p) module_param_hw_named(n, v, t, hwtype, p) module_param_hw_array(n, t, hwtype, m, p) where the module parameter refers to a hardware setting hwtype specifies the type of the resource being configured. This can be one of: ioport Module parameter configures an I/O port iomem Module parameter configures an I/O mem address ioport_or_iomem Module parameter could be either (runtime set) irq Module parameter configures an I/O port dma Module parameter configures a DMA channel dma_addr Module parameter configures a DMA buffer address other Module parameter configures some other value Note that the hwtype is compile checked, but not currently stored (the lockdown code probably won't require it). It is, however, there for future use. A bonus is that the hwtype can also be used for grepping. The intention is for the kernel to ignore or reject attempts to set annotated module parameters if lockdown is enabled. This applies to options passed on the boot command line, passed to insmod/modprobe or direct twiddling in /sys/module/ parameter files. The module initialisation then needs to handle the parameter not being set, by (1) giving an error, (2) probing for a value or (3) using a reasonable default. What I can't do is just reject a module out of hand because it may take a hardware setting in the module parameters. Some important modules, some ipmi stuff for instance, both probe for hardware and allow hardware to be manually specified; if the driver is aborts with any error, you don't get any ipmi hardware. Further, trying to do this entirely in the module initialisation code doesn't protect against sysfs twiddling. [!] Note that in and of itself, this series of patches should have no effect on the the size of the kernel or code execution - that is left to a patch in the next series to effect. It does mark annotated kernel parameters with a KERNEL_PARAM_FL_HWPARAM flag in an already existing field" * tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (38 commits) Annotate hardware config module parameters in sound/pci/ Annotate hardware config module parameters in sound/oss/ Annotate hardware config module parameters in sound/isa/ Annotate hardware config module parameters in sound/drivers/ Annotate hardware config module parameters in fs/pstore/ Annotate hardware config module parameters in drivers/watchdog/ Annotate hardware config module parameters in drivers/video/ Annotate hardware config module parameters in drivers/tty/ Annotate hardware config module parameters in drivers/staging/vme/ Annotate hardware config module parameters in drivers/staging/speakup/ Annotate hardware config module parameters in drivers/staging/media/ Annotate hardware config module parameters in drivers/scsi/ Annotate hardware config module parameters in drivers/pcmcia/ Annotate hardware config module parameters in drivers/pci/hotplug/ Annotate hardware config module parameters in drivers/parport/ Annotate hardware config module parameters in drivers/net/wireless/ Annotate hardware config module parameters in drivers/net/wan/ Annotate hardware config module parameters in drivers/net/irda/ Annotate hardware config module parameters in drivers/net/hamradio/ Annotate hardware config module parameters in drivers/net/ethernet/ ...
2017-05-08Merge tag 'tty-4.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial updates from Greg KH: "Here is the "big" TTY/Serial patch updates for 4.12-rc1 Not a lot of new things here, the normal number of serial driver updates and additions, tiny bugs fixed, and some core files split up to make future changes a bit easier for Nicolas's "tiny-tty" work. All of these have been in linux-next for a while" * tag 'tty-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (62 commits) serial: small Makefile reordering tty: split job control support into a file of its own tty: move baudrate handling code to a file of its own console: move console_init() out of tty_io.c serial: 8250_early: Add earlycon support for Palmchip UART tty: pl011: use "qdf2400_e44" as the earlycon name for QDF2400 E44 vt: make mouse selection of non-ASCII consistent vt: set mouse selection word-chars to gpm's default imx-serial: Reduce RX DMA startup latency when opening for reading serial: omap: suspend device on probe errors serial: omap: fix runtime-pm handling on unbind tty: serial: omap: add UPF_BOOT_AUTOCONF flag for DT init serial: samsung: Remove useless spinlock serial: samsung: Add missing checks for dma_map_single failure serial: samsung: Use right device for DMA-mapping calls serial: imx: setup DCEDTE early and ensure DCD and RI irqs to be off tty: fix comment typo s/repsonsible/responsible/ tty: amba-pl011: Fix spurious TX interrupts serial: xuartps: Enable clocks in the pm disable case also serial: core: Re-use struct uart_port {name} field ...
2017-05-08format-security: move static strings to constKees Cook
While examining output from trial builds with -Wformat-security enabled, many strings were found that should be defined as "const", or as a char array instead of char pointer. This makes some static analysis easier, by producing fewer false positives. As these are all trivial changes, it seemed best to put them all in a single patch rather than chopping them up per maintainer. Link: http://lkml.kernel.org/r/20170405214711.GA5711@beast Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Jes Sorensen <jes@trained-monkey.org> [runner.c] Cc: Tony Lindgren <tony@atomide.com> Cc: Russell King <linux@armlinux.org.uk> Cc: "Maciej W. Rozycki" <macro@linux-mips.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Sean Paul <seanpaul@chromium.org> Cc: David Airlie <airlied@linux.ie> Cc: Yisen Zhuang <yisen.zhuang@huawei.com> Cc: Salil Mehta <salil.mehta@huawei.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Jiri Slaby <jslaby@suse.com> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Mugunthan V N <mugunthanvnm@ti.com> Cc: Felipe Balbi <felipe.balbi@linux.intel.com> Cc: Jarod Wilson <jarod@redhat.com> Cc: Florian Westphal <fw@strlen.de> Cc: Antonio Quartulli <a@unstable.cc> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Kejian Yan <yankejian@huawei.com> Cc: Daode Huang <huangdaode@hisilicon.com> Cc: Qianqian Xie <xieqianqian@huawei.com> Cc: Philippe Reynes <tremyfr@gmail.com> Cc: Colin Ian King <colin.king@canonical.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Christian Gromm <christian.gromm@microchip.com> Cc: Andrey Shvetsov <andrey.shvetsov@k2l.de> Cc: Jason Litzinger <jlitzingerdev@gmail.com> Cc: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-05Merge tag 'devicetree-for-4.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull DeviceTree updates from Rob Herring: - fix sparse warnings in drivers/of/ - add more overlay unittests - update dtc to v1.4.4-8-g756ffc4f52f6. This adds more checks on dts files such as unit-address formatting and stricter character sets for node and property names - add a common DT modalias function - move trivial-devices.txt up and out of i2c dir - ARM NVIC interrupt controller binding - vendor prefixes for Sensirion, Dioo, Nordic, ROHM - correct some binding file locations * tag 'devicetree-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (24 commits) of: fix sparse warnings in fdt, irq, reserved mem, and resolver code of: fix sparse warning in of_pci_range_parser_one of: fix sparse warnings in of_find_next_cache_node of/unittest: Missing unlocks on error of: fix uninitialized variable warning for overlay test of: fix unittest build without CONFIG_OF_OVERLAY of: Add unit tests for applying overlays of: per-file dtc compiler flags fpga: region: add missing DT documentation for config complete timeout of: Add vendor prefix for ROHM Semiconductor of: fix "/cpus" reference leak in of_numa_parse_cpu_nodes() of: Add vendor prefix for Nordic Semiconductor dt-bindings: arm,nvic: Binding for ARM NVIC interrupt controller on Cortex-M dtc: update warning settings for new bus and node/property name checks scripts/dtc: Update to upstream version v1.4.4-8-g756ffc4f52f6 scripts/dtc: automate getting dtc version and log in update script of: Add function for generating a DT modalias with a newline of: fix of_device_get_modalias returned length when truncating buffers Documentation: devicetree: move trivial-devices out of I2C realm dt-bindings: add vendor prefix for Dioo ..
2017-05-03oom: improve oom disable handlingMichal Hocko
Tetsuo has reported that sysrq triggered OOM killer will print a misleading information when no tasks are selected: sysrq: SysRq : Manual OOM execution Out of memory: Kill process 4468 ((agetty)) score 0 or sacrifice child Killed process 4468 ((agetty)) total-vm:43704kB, anon-rss:1760kB, file-rss:0kB, shmem-rss:0kB sysrq: SysRq : Manual OOM execution Out of memory: Kill process 4469 (systemd-cgroups) score 0 or sacrifice child Killed process 4469 (systemd-cgroups) total-vm:10704kB, anon-rss:120kB, file-rss:0kB, shmem-rss:0kB sysrq: SysRq : Manual OOM execution sysrq: OOM request ignored because killer is disabled sysrq: SysRq : Manual OOM execution sysrq: OOM request ignored because killer is disabled sysrq: SysRq : Manual OOM execution sysrq: OOM request ignored because killer is disabled The real reason is that there are no eligible tasks for the OOM killer to select but since commit 7c5f64f84483 ("mm: oom: deduplicate victim selection code for memcg and global oom") the semantic of out_of_memory has changed without updating moom_callback. This patch updates moom_callback to tell that no task was eligible which is the case for both oom killer disabled and no eligible tasks. In order to help distinguish first case from the second add printk to both oom_killer_{enable,disable}. This information is useful on its own because it might help debugging potential memory allocation failures. Fixes: 7c5f64f84483 ("mm: oom: deduplicate victim selection code for memcg and global oom") Link: http://lkml.kernel.org/r/20170404134705.6361-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-02Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: tty: fix comment for __tty_alloc_driver() init/main: properly align the multi-line comment init/main: Fix double "the" in comment Fix dead URLs to ftp.kernel.org drivers: Clean up duplicated email address treewide: Fix typo in xml/driver-api/basics.xml tools/testing/selftests/powerpc: remove redundant CFLAGS in Makefile: "-Wall -O2 -Wall" -> "-O2 -Wall" selftests/timers: Spelling s/privledges/privileges/ HID: picoLCD: Spelling s/REPORT_WRTIE_MEMORY/REPORT_WRITE_MEMORY/ net: phy: dp83848: Fix Typo UBI: Fix typos Documentation: ftrace.txt: Correct nice value of 120 priority net: fec: Fix typo in error msg and comment treewide: Fix typos in printk
2017-04-24tty: fix comment for __tty_alloc_driver()Thadeu Lima de Souza Cascardo
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@cascardo.eti.br> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-04-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
A function in kernel/bpf/syscall.c which got a bug fix in 'net' was moved to kernel/bpf/verifier.c in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-20Annotate hardware config module parameters in drivers/tty/David Howells
When the kernel is running in secure boot mode, we lock down the kernel to prevent userspace from modifying the running kernel image. Whilst this includes prohibiting access to things like /dev/mem, it must also prevent access by means of configuring driver modules in such a way as to cause a device to access or modify the kernel image. To this end, annotate module_param* statements that refer to hardware configuration and indicate for future reference what type of parameter they specify. The parameter parser in the core sees this information and can skip such parameters with an error message if the kernel is locked down. The module initialisation then runs as normal, but just sees whatever the default values for those parameters is. Note that we do still need to do the module initialisation because some drivers have viable defaults set in case parameters aren't specified and some drivers support automatic configuration (e.g. PNP or PCI) in addition to manually coded parameters. This patch annotates drivers in drivers/tty/. Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> cc: Jiri Slaby <jslaby@suse.com> cc: linux-serial@vger.kernel.org
2017-04-18serial: small Makefile reorderingNicolas Pitre
Move 21285 entry down alongside other UART drivers to be more consistent with the rest of the file. It is kept before 8250 though, to preserve the existing link ordering between those two. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-18tty: split job control support into a file of its ownNicolas Pitre
This makes it easier for job control to become optional and/or usable independently from tty_io.c, as well as providing a nice purpose separation. No logical changes from this patch. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-18tty: move baudrate handling code to a file of its ownNicolas Pitre
To allow reuse without the rest of the tty_ioctl code. No logical changes from this patch. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-18console: move console_init() out of tty_io.cNicolas Pitre
All the console driver handling code lives in printk.c. Move console_init() there as well so console support can still be used when the TTY code is configured out. No logical changes from this patch. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>