The driver calls ioremap() in the probe function but doesn't call
iounmap() in the remove function correspondingly. Do so now.
Follow commit 5c9d6abed9 ("serial: altera_jtaguart: adding iounmap()")
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit e61c38d85b ("serial: imx: setup DCEDTE early and ensure DCD and
RI irqs to be off") has a flaw: While UCR3 and UFCR were modified using
read-modify-write before it switched to write register values
independent of the previous state. That's a good idea in principle (and
that's why I did it) but needs more care.
This patch reinstates read-modify-write for UFCR and for UCR3 ensures
that RXDMUXSEL and ADNIMP are set for post imx1.
Fixes: e61c38d85b ("serial: imx: setup DCEDTE early and ensure DCD and RI irqs to be off")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Mika Penttilä <mika.penttila@nextfour.com>
Tested-by: Mika Penttilä <mika.penttila@nextfour.com>
Acked-by: Steve Twiss <stwiss.opensource@diasemi.com>
Tested-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
Starting with commit 6fe729c4bd ("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: 6fe729c4bd ("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>
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: 8ee3fde047 (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>
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>
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>
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: 72d4724ea5 ("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>
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>
After migrating 8250_exar to MSI in 172c33cb61, 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: 172c33cb61 ("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>
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: 3afbd89c96 ("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>
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: bed35c6dfa ("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>
This reverts commit 8ee3fde047.
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>
Commit fa01e2ca9f ("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: fa01e2ca9f ("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>
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/
...
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
...
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
..
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 7c5f64f844 ("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: 7c5f64f844 ("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>
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>
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
