[ Upstream commit 66aad7d8d3 ]
In ACM support for sending breaks to devices is optional.
If a device says that it doenot support sending breaks,
the host must respect that.
Given the number of optional features providing tty operations
for each combination is not practical and errors need to be
returned dynamically if unsupported features are requested.
In case a device does not support break, we want the tty layer
to treat that like it treats drivers that statically cannot
support sending a break. It ignores the inability and does nothing.
This patch uses EOPNOTSUPP to indicate that.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Fixes: 9e98966c7b ("tty: rework break handling")
Link: https://lore.kernel.org/r/20231207132639.18250-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 24f2cd0199 ]
Now, the "jumped-over" code is simple enough to be put inside an 'if'.
Do so to make it 'goto'-less.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230919085156.1578-16-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 66aad7d8d3 ("usb: cdc-acm: return correct error code on unsupported break")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fd99392b64 ]
msleep_interruptible() will check on its own. So no need to do the check
in send_break() before calling the above.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230919085156.1578-15-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 66aad7d8d3 ("usb: cdc-acm: return correct error code on unsupported break")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 66619686d1 ]
If the driver sets TTY_DRIVER_HARDWARE_BREAK, we leave ops->break_ctl()
to the driver and return from send_break(). But we do it using a local
variable and keep the code flowing through the end of the function.
Instead, do 'return' immediately with the ops->break_ctl()'s return
value.
This way, we don't have to stuff the 'else' branch of the 'if' with the
software break handling. And we can re-indent the function too.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230919085156.1578-14-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 66aad7d8d3 ("usb: cdc-acm: return correct error code on unsupported break")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 78d60dae9a ]
When using the serial port as RS485 port, the tx statemachine is used to
control the RTS pin to drive the RS485 transceiver TX_EN pin. When the
TTY port is closed in the middle of a transmission (for instance during
userland application crash), imx_uart_shutdown disables the interface
and disables the Transmission Complete interrupt. afer that,
imx_uart_stop_tx bails on an incomplete transmission, to be retriggered
by the TC interrupt. This interrupt is disabled and therefore the tx
statemachine never transitions out of SEND. The statemachine is in
deadlock now, and the TX_EN remains low, making the interface useless.
imx_uart_stop_tx now checks for incomplete transmission AND whether TC
interrupts are enabled before bailing to be retriggered. This makes sure
the state machine handling is reached, and is properly set to
WAIT_AFTER_SEND.
Fixes: cb1a609236 ("serial: imx: implement rts delaying for rs485")
Signed-off-by: Paul Geurts <paul_geurts@live.nl>
Tested-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Tested-by: Eberhard Stoll <eberhard.stoll@gmx.de>
Link: https://lore.kernel.org/r/AM0PR09MB26758F651BC1B742EB45775995B8A@AM0PR09MB2675.eurprd09.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ad90d0358b ]
Returning an error code from .remove() makes the driver core emit the
little helpful error message:
remove callback returned a non-zero value. This will be ignored.
and then remove the device anyhow. So all resources that were not freed
are leaked in this case. Skipping serial8250_unregister_port() has the
potential to keep enough of the UART around to trigger a use-after-free.
So replace the error return (and with it the little helpful error
message) by a more useful error message and continue to cleanup.
Fixes: e3f0c638f4 ("serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove()")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20231110152927.70601-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 3ef79cd141 upstream.
15 MHz is supported only by 76x variants.
If the SPI clock frequency is not specified, use a safe default clock value
of 4 MHz that is supported by all variants.
Also use HZ_PER_MHZ macro to improve readability.
Fixes: 2c837a8a8f ("sc16is7xx: spi interface is added")
Cc: <stable@vger.kernel.org>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231221231823.2327894-4-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6d710b769c upstream.
The original comment is confusing because it implies that variants other
than the SC16IS762 supports other SPI modes beside SPI_MODE_0.
Extract from datasheet:
The SC16IS762 differs from the SC16IS752 in that it supports SPI clock
speeds up to 15 Mbit/s instead of the 4 Mbit/s supported by the
SC16IS752... In all other aspects, the SC16IS762 is functionally and
electrically the same as the SC16IS752.
The same is also true of the SC16IS760 variant versus the SC16IS740 and
SC16IS750 variants.
For all variants, only SPI mode 0 is supported.
Change comment and abort probing if the specified SPI mode is not
SPI_MODE_0.
Fixes: 2c837a8a8f ("sc16is7xx: spi interface is added")
Cc: <stable@vger.kernel.org>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231221231823.2327894-3-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 51f93776b8 upstream.
The drivers RS485 support is deactivated if there is no RTS GPIO available.
This is done by nullifying the ports rs485_supported struct. After that
however the settings in serial_omap_rs485_supported are assigned to the
same structure unconditionally, which results in an unintended reactivation
of RS485 support.
Fix this by moving the assignment to the beginning of
serial_omap_probe_rs485() and thus before uart_get_rs485_mode() gets
called.
Also replace the assignment of rs485_config() to have the complete RS485
setup in one function.
Fixes: e2752ae3cf ("serial: omap: Disallow RS-485 if rts-gpio is not specified")
Cc: <stable@vger.kernel.org>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240103061818.564-7-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0c2a5f471c upstream.
The UART supports an auto-RTS mode in which the RTS pin is automatically
activated during transmission. So mark this mode as being supported even
if RTS is not controlled by the driver but the UART.
Also the serial core expects now at least one of both modes rts-on-send or
rts-after-send to be supported. This is since during sanitization
unsupported flags are deleted from a RS485 configuration set by userspace.
However if the configuration ends up with both flags unset, the core prints
a warning since it considers such a configuration invalid (see
uart_sanitize_serial_rs485()).
Cc: <stable@vger.kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20240103061818.564-8-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7c45eaa813 upstream.
There are register accesses in the function imx_uart_rs485_config(). The
clock must be enabled for these accesses. This was ensured by calling it
via the function uart_rs485_config() in the probe() function within the
range where the clock is enabled. With the commit 7c7f9bc986 ("serial:
Deassert Transmit Enable on probe in driver-specific way") it was removed
from the probe() function and is now only called through the function
uart_add_one_port() which is located at the end of the probe() function.
But the clock is already switched off in this area. To ensure that the
clock is enabled during register access, move the disabling of the clock
to the very end of the probe() function. To avoid leaking enabled clocks
on error also add an error path for exiting with disabling the clock.
Fixes: 7c7f9bc986 ("serial: Deassert Transmit Enable on probe in driver-specific way")
Cc: stable <stable@kernel.org>
Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/20231226113647.39376-1-cniedermaier@dh-electronics.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 74eab89b26 upstream.
If the imx driver cannot support RS485 it nullifies the ports
rs485_supported structure. But it still calls uart_get_rs485_mode() which
may set the RS485_ENABLED flag nevertheless.
This may lead to an attempt to configure RS485 even if it is not supported
when the flag is evaluated in uart_configure_port() at port startup.
Avoid this by bailing out of uart_get_rs485_mode() if the RS485_ENABLED
flag is not supported by the caller.
With this fix a check for RTS availability is now obsolete in the imx
driver, since it can not evaluate to true any more. So remove this check.
Furthermore the explicit nullifcation of rs485_supported is not needed,
since the memory has already been set to zeros at allocation. So remove
this, too.
Fixes: 00d7a00e2a ("serial: imx: Fill in rs485_supported")
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: <stable@vger.kernel.org>
Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240103061818.564-6-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c73986913f upstream.
Some uart drivers specify a rs485_config() function and then decide later
to disable RS485 support for some reason (e.g. imx and ar933).
In these cases userspace may be able to activate RS485 via TIOCSRS485
nevertheless, since in uart_set_rs485_config() an existing rs485_config()
function indicates that RS485 is supported.
Make sure that this is not longer possible by checking the uarts
rs485_supported.flags instead and bailing out if SER_RS485_ENABLED is not
set.
Furthermore instead of returning an empty structure return -ENOTTY if the
RS485 configuration is requested via TIOCGRS485 but RS485 is not supported.
This has a small impact on userspace visibility but it is consistent with
the -ENOTTY error for TIOCGRS485.
Fixes: e849145e1f ("serial: ar933x: Fill in rs485_supported")
Fixes: 55e18c6b6d ("serial: imx: Remove serial_rs485 sanitization")
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: <stable@vger.kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20240103061818.564-5-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4afeced55b upstream.
Among other things uart_sanitize_serial_rs485() tests the sanity of the RTS
settings in a RS485 configuration that has been passed by userspace.
If RTS-on-send and RTS-after-send are both set or unset the configuration
is adjusted and RTS-after-send is disabled and RTS-on-send enabled.
This however makes only sense if both RTS modes are actually supported by
the driver.
With commit be2e2cb1d2 ("serial: Sanitize rs485_struct") the code does
take the driver support into account but only checks if one of both RTS
modes are supported. This may lead to the errorneous result of RTS-on-send
being set even if only RTS-after-send is supported.
Fix this by changing the implemented logic: First clear all unsupported
flags in the RS485 configuration, then adjust an invalid RTS setting by
taking into account which RTS mode is supported.
Cc: <stable@vger.kernel.org>
Fixes: be2e2cb1d2 ("serial: Sanitize rs485_struct")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20240103061818.564-4-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8e42c301ce upstream.
Currently there is no support for earlycon on the AM654 UART
controller. This commit adds it.
Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20231031131242.15516-1-rwahl@gmx.de
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c6bb057418 upstream.
Starting RX DMA on THRI interrupt is too early because TX may not have
finished yet.
This change is inspired by commit 90b8596ac4 ("serial: 8250: Prevent
starting up DMA Rx on THRI interrupt") and fixes DMA issues I had with
an AM62 SoC that is using the 8250 OMAP variant.
Cc: stable@vger.kernel.org
Fixes: c26389f998 ("serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs")
Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20231101171431.16495-1-rwahl@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8973ab7a24 upstream.
This fixes commit 439c7183e5 ("serial: 8250: 8250_omap: Disable RX
interrupt after DMA enable") which unfortunately set the
UART_HAS_RHR_IT_DIS bit in the UART_OMAP_IER2 register and never
cleared it.
Cc: stable@vger.kernel.org
Fixes: 439c7183e5 ("serial: 8250: 8250_omap: Disable RX interrupt after DMA enable")
Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20231031110909.11695-1-rwahl@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 08ce9a1b72 upstream.
This device has a silicon bug that makes it report a timeout interrupt
but no data in the FIFO.
The datasheet states the following in the errata section 18.1.4:
"If the host reads the receive FIFO at the same time as a
time-out interrupt condition happens, the host might read 0xCC
(time-out) in the Interrupt Indication Register (IIR), but bit 0
of the Line Status Register (LSR) is not set (means there is no
data in the receive FIFO)."
The errata description seems to indicate it concerns only polled mode of
operation when reading bit 0 of the LSR register. However, tests have
shown and NXP has confirmed that the RXLVL register also yields 0 when
the bug is triggered, and hence the IRQ driven implementation in this
driver is equally affected.
This bug has hit us on production units and when it does, sc16is7xx_irq()
would spin forever because sc16is7xx_port_irq() keeps seeing an
interrupt in the IIR register that is not cleared because the driver
does not call into sc16is7xx_handle_rx() unless the RXLVL register
reports at least one byte in the FIFO.
Fix this by always reading one byte from the FIFO when this condition
is detected in order to clear the interrupt. This approach was
confirmed to be correct by NXP through their support channels.
Tested by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Signed-off-by: Daniel Mack <daniel@zonque.org>
Co-Developed-by: Maxim Popov <maxim.snafu@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20231123072818.1394539-1-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 58ac1b3799 upstream.
Since there is no guarantee that the memory returned by
dma_alloc_coherent() is associated with a 'struct page', using the
architecture specific phys_to_page() is wrong, but using
virt_to_page() would be as well.
Stop using sg lists altogether and just use the *_single() functions
instead. This also simplifies the code a bit since the scatterlists in
this driver always have only one entry anyway.
https://lore.kernel.org/lkml/86db0fe5-930d-4cbb-bd7d-03367da38951@app.fastmail.com/
Use consistent names for dma buffers
gc: Add a commit log from the initial thread:
https://lore.kernel.org/lkml/86db0fe5-930d-4cbb-bd7d-03367da38951@app.fastmail.com/
Use consistent names for dma buffers
Fixes: cb06ff102e ("ARM: PL011: Add support for Rx DMA buffer polling.")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20231122171503.235649-1-gregory.clement@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b4a778303e upstream.
Retrieve rs485 devicetree properties on registration of sc16is7xx ports in
case they are attached to an rs485 transceiver.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Lech Perczak <lech.perczak@camlingroup.com>
Tested-by: Lech Perczak <lech.perczak@camlingroup.com>
Link: https://lore.kernel.org/r/20230807214556.540627-7-hugo@hugovil.com
Cc: Hugo Villeneuve <hugo@hugovil.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 77a82cebf0 upstream.
According to the IOControl register bits description in the page 31 of
the product datasheet, we know the bit 3 of IOControl register is
softreset, this bit will self-clearing once the reset finish.
In the probe, the softreset bit is set, and when we read this register
from debugfs/regmap interface, we found the softreset bit is still
setting, this confused us for a while. Finally we found this register
is cached, to read the real value from register, we could put it
into the regmap_volatile().
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Link: https://lore.kernel.org/r/20230724034727.17335-1-hui.wang@canonical.com
Cc: Hugo Villeneuve <hugo@hugovil.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ef5dd8ec88 upstream.
The xencons_connect_backend() function allocates a local interdomain
event channel with xenbus_alloc_evtchn(), then calls
bind_interdomain_evtchn_to_irq_lateeoi() to bind to that port# on the
*remote* domain.
That doesn't work very well:
(qemu) device_add xen-console,id=con1,chardev=pty0
[ 44.323872] xenconsole console-1: 2 xenbus_dev_probe on device/console/1
[ 44.323995] xenconsole: probe of console-1 failed with error -2
Fix it to use bind_evtchn_to_irq_lateeoi(), which does the right thing
by just binding that *local* event channel to an irq. The backend will
do the interdomain binding.
This didn't affect the primary console because the setup for that is
special — the toolstack allocates the guest event channel and the guest
discovers it with HVMOP_get_param.
Fixes: fe415186b4 ("xen/console: harden hvc_xen against event channel storms")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20231020161529.355083-2-dwmw2@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2704c9a559 upstream.
The xen_hvc_init() function should always register the frontend driver,
even when there's no primary console — as there may be secondary consoles.
(Qemu can always add secondary consoles, but only the toolstack can add
the primary because it's special.)
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20231020161529.355083-3-dwmw2@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a30badfd7c upstream.
On unplug of a Xen console, xencons_disconnect_backend() unconditionally
calls free_irq() via unbind_from_irqhandler(), causing a warning of
freeing an already-free IRQ:
(qemu) device_del con1
[ 32.050919] ------------[ cut here ]------------
[ 32.050942] Trying to free already-free IRQ 33
[ 32.050990] WARNING: CPU: 0 PID: 51 at kernel/irq/manage.c:1895 __free_irq+0x1d4/0x330
It should be using evtchn_put() to tear down the event channel binding,
and let the Linux IRQ side of it be handled by notifier_del_irq() through
the HVC code.
On which topic... xencons_disconnect_backend() should call hvc_remove()
*first*, rather than tearing down the event channel and grant mapping
while they are in use. And then the IRQ is guaranteed to be freed by
the time it's torn down by evtchn_put().
Since evtchn_put() also closes the actual event channel, avoid calling
xenbus_free_evtchn() except in the failure path where the IRQ was not
successfully set up.
However, calling hvc_remove() at the start of xencons_disconnect_backend()
still isn't early enough. An unplug request is indicated by the backend
setting its state to XenbusStateClosing, which triggers a notification
to xencons_backend_changed(), which... does nothing except set its own
frontend state directly to XenbusStateClosed without *actually* tearing
down the HVC device or, you know, making sure it isn't actively in use.
So the backend sees the guest frontend set its state to XenbusStateClosed
and stops servicing the interrupt... and the guest spins for ever in the
domU_write_console() function waiting for the ring to drain.
Fix that one by calling hvc_remove() from xencons_backend_changed() before
signalling to the backend that it's OK to proceed with the removal.
Tested with 'dd if=/dev/zero of=/dev/hvc1' while telling Qemu to remove
the console device.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20231020161529.355083-4-dwmw2@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dd976a97d1 upstream.
The smp_processor_id() shouldn't be called from preemptible code.
Instead use get_cpu() and put_cpu() which disables preemption in
addition to getting the processor id. Enable preemption back after
calling schedule_work() to make sure that the work gets scheduled on all
cores other than the current core. We want to avoid a scenario where
current core's stack trace is printed multiple times and one core's
stack trace isn't printed because of scheduling of current task.
This fixes the following bug:
[ 119.143590] sysrq: Show backtrace of all active CPUs
[ 119.143902] BUG: using smp_processor_id() in preemptible [00000000] code: bash/873
[ 119.144586] caller is debug_smp_processor_id+0x20/0x30
[ 119.144827] CPU: 6 PID: 873 Comm: bash Not tainted 5.10.124-dirty #3
[ 119.144861] Hardware name: QEMU QEMU Virtual Machine, BIOS 2023.05-1 07/22/2023
[ 119.145053] Call trace:
[ 119.145093] dump_backtrace+0x0/0x1a0
[ 119.145122] show_stack+0x18/0x70
[ 119.145141] dump_stack+0xc4/0x11c
[ 119.145159] check_preemption_disabled+0x100/0x110
[ 119.145175] debug_smp_processor_id+0x20/0x30
[ 119.145195] sysrq_handle_showallcpus+0x20/0xc0
[ 119.145211] __handle_sysrq+0x8c/0x1a0
[ 119.145227] write_sysrq_trigger+0x94/0x12c
[ 119.145247] proc_reg_write+0xa8/0xe4
[ 119.145266] vfs_write+0xec/0x280
[ 119.145282] ksys_write+0x6c/0x100
[ 119.145298] __arm64_sys_write+0x20/0x30
[ 119.145315] el0_svc_common.constprop.0+0x78/0x1e4
[ 119.145332] do_el0_svc+0x24/0x8c
[ 119.145348] el0_svc+0x10/0x20
[ 119.145364] el0_sync_handler+0x134/0x140
[ 119.145381] el0_sync+0x180/0x1c0
Cc: jirislaby@kernel.org
Cc: stable@vger.kernel.org
Fixes: 47cab6a722 ("debug lockups: Improve lockup detection, fix generic arch fallback")
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/r/20231009162021.3607632-1-usama.anjum@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d81ffb87aa ]
Add check for the return value of kstrdup() and return the error, if it
fails in order to avoid NULL pointer dereference.
Signed-off-by: Yi Yang <yiyang13@huawei.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230904035220.48164-1-yiyang13@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 11e7f27b79 ]
There is a pid leakage:
------------------------------
unreferenced object 0xffff88810c181940 (size 224):
comm "sshd", pid 8191, jiffies 4294946950 (age 524.570s)
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 ad 4e ad de .............N..
ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........
backtrace:
[<ffffffff814774e6>] kmem_cache_alloc+0x5c6/0x9b0
[<ffffffff81177342>] alloc_pid+0x72/0x570
[<ffffffff81140ac4>] copy_process+0x1374/0x2470
[<ffffffff81141d77>] kernel_clone+0xb7/0x900
[<ffffffff81142645>] __se_sys_clone+0x85/0xb0
[<ffffffff8114269b>] __x64_sys_clone+0x2b/0x30
[<ffffffff83965a72>] do_syscall_64+0x32/0x80
[<ffffffff83a00085>] entry_SYSCALL_64_after_hwframe+0x61/0xc6
It turns out that there is a race condition between disassociate_ctty() and
tty_signal_session_leader(), which caused this leakage.
The pid memleak is triggered by the following race:
task[sshd] task[bash]
----------------------- -----------------------
disassociate_ctty();
spin_lock_irq(¤t->sighand->siglock);
put_pid(current->signal->tty_old_pgrp);
current->signal->tty_old_pgrp = NULL;
tty = tty_kref_get(current->signal->tty);
spin_unlock_irq(¤t->sighand->siglock);
tty_vhangup();
tty_lock(tty);
...
tty_signal_session_leader();
spin_lock_irq(&p->sighand->siglock);
...
if (tty->ctrl.pgrp) //tty->ctrl.pgrp is not NULL
p->signal->tty_old_pgrp = get_pid(tty->ctrl.pgrp); //An extra get
spin_unlock_irq(&p->sighand->siglock);
...
tty_unlock(tty);
if (tty) {
tty_lock(tty);
...
put_pid(tty->ctrl.pgrp);
tty->ctrl.pgrp = NULL; //It's too late
...
tty_unlock(tty);
}
The issue is believed to be introduced by commit c8bcd9c5be ("tty:
Fix ->session locking") who moves the unlock of siglock in
disassociate_ctty() above "if (tty)", making a small window allowing
tty_signal_session_leader() to kick in. It can be easily reproduced by
adding a delay before "if (tty)" and at the entrance of
tty_signal_session_leader().
To fix this issue, we move "put_pid(current->signal->tty_old_pgrp)" after
"tty->ctrl.pgrp = NULL".
Fixes: c8bcd9c5be ("tty: Fix ->session locking")
Signed-off-by: Yi Yang <yiyang13@huawei.com>
Co-developed-by: GUO Zihua <guozihua@huawei.com>
Signed-off-by: GUO Zihua <guozihua@huawei.com>
Link: https://lore.kernel.org/r/20230831023329.165737-1-yiyang13@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e4876dacac upstream.
Some of the later revisions of the Brainboxes PX cards are based
on the Oxford Semiconductor chipset. Due to the chip's unique setup
these cards need to be initialised.
Previously these were tested against a reference card with the same broken
baudrate on another PC, cancelling out the effect. With this patch they
work and can transfer/receive find against an FTDI-based device.
Add all of the cards which require this setup to the quirks table.
Thanks to Maciej W. Rozycki for clarification on this chip.
Fixes: ef5a03a26c ("tty: 8250: Add support for Brainboxes PX cards.")
Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams <cang1@live.co.uk>
Link: https://lore.kernel.org/r/DU0PR02MB7899D222A4AB2A4E8C57108FC4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 33092fb3af upstream.
The UC-257 is a serial + LPT card, so remove it from this driver.
A patch has been submitted to add it to parport_serial instead.
Additionaly, the UC-431 does not use this card ID, only the UC-420
does. The 431 is a 3-port card and there is no generic 3-port configuration
available, so remove reference to it from this driver.
Fixes: 152d1afa83 ("tty: Add support for Brainboxes UC cards.")
Cc: stable@vger.kernel.org
Signed-off-by: Cameron Williams <cang1@live.co.uk>
Link: https://lore.kernel.org/r/DU0PR02MB78995ADF7394C74AD4CF3357C4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3a75b205de upstream.
gsm_cleanup_mux() cleans up the gsm by closing all DLCIs, stopping all
timers, removing the virtual tty devices and clearing the data queues.
This procedure, however, may cause subsequent changes of the virtual modem
status lines of a DLCI. More data is being added the outgoing data queue
and the deleted kick timer is restarted to handle this. At this point many
resources have already been removed by the cleanup procedure. Thus, a
kernel panic occurs.
Fix this by proving in gsm_modem_update() that the cleanup procedure has
not been started and the mux is still alive.
Note that writing to a virtual tty is already protected by checks against
the DLCI specific connection state.
Fixes: c568f7086c ("tty: n_gsm: fix missing timer to handle stalled links")
Cc: stable <stable@kernel.org>
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20231026055844.3127-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ae62c49c0c upstream.
The new uart_write() function is only called from suspend/resume code, causing
a build warning when those are left out:
drivers/tty/serial/8250/8250_omap.c:169:13: error: 'uart_write' defined but not used [-Werror=unused-function]
Remove the #ifdefs and use the modern pm_ops/pm_sleep_ops and their wrappers
to let the compiler see where it's used but still drop the dead code.
Fixes: 398cecc248 ("serial: 8250: omap: Fix imprecise external abort for omap_8250_pm()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230517202012.634386-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 560706eff7 ]
We now get errors on system suspend if no_console_suspend is set as
reported by Thomas. The errors started with commit 20a41a6261 ("serial:
8250_omap: Use force_suspend and resume for system suspend").
Let's fix the issue by checking for console_suspend_enabled in the system
suspend and resume path.
Note that with this fix the checks for console_suspend_enabled in
omap8250_runtime_suspend() become useless. We now keep runtime PM usage
count for an attached kernel console starting with commit bedb404e91
("serial: 8250_port: Don't use power management for kernel console").
Fixes: 20a41a6261 ("serial: 8250_omap: Use force_suspend and resume for system suspend")
Cc: stable <stable@kernel.org>
Cc: Udit Kumar <u-kumar1@ti.com>
Reported-by: Thomas Richard <thomas.richard@bootlin.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Thomas Richard <thomas.richard@bootlin.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20230926061319.15140-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 398cecc248 ]
We must idle the uart only after serial8250_unregister_port(). Otherwise
unbinding the uart via sysfs while doing cat on the port produces an
imprecise external abort:
mem_serial_in from omap_8250_pm+0x44/0xf4
omap_8250_pm from uart_hangup+0xe0/0x194
uart_hangup from __tty_hangup.part.0+0x37c/0x3a8
__tty_hangup.part.0 from uart_remove_one_port+0x9c/0x22c
uart_remove_one_port from serial8250_unregister_port+0x60/0xe8
serial8250_unregister_port from omap8250_remove+0x6c/0xd0
omap8250_remove from platform_remove+0x28/0x54
Turns out the driver needs to have runtime PM functional before the
driver probe calls serial8250_register_8250_port(). And it needs
runtime PM after driver remove calls serial8250_unregister_port().
On probe, we need to read registers before registering the port in
omap_serial_fill_features_erratas(). We do that with custom uart_read()
already.
On remove, after serial8250_unregister_port(), we need to write to the
uart registers to idle the device. Let's add a custom uart_write() for
that.
Currently the uart register access depends on port->membase to be
initialized, which won't work after serial8250_unregister_port().
Let's use priv->membase instead, and use it for runtime PM related
functions to remove the dependency to port->membase for early and
late register access.
Note that during use, we need to check for a valid port in the runtime PM
related functions. This is needed for the optional wakeup configuration.
We now need to set the drvdata a bit earlier so it's available for the
runtime PM functions.
With the port checks in runtime PM functions, the old checks for priv in
omap8250_runtime_suspend() and omap8250_runtime_resume() functions are no
longer needed and are removed.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230508082014.23083-3-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 560706eff7 ("serial: 8250_omap: Fix errors with no_console_suspend")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8679328eb8 ]
Commit 44b27aec9d ("serial: core, 8250: set RS485 termination GPIO in
serial core") enabled support for RS485 termination GPIOs behind i2c
expanders by setting the GPIO outside of the critical section protected
by the port spinlock. Access to the i2c expander may sleep, which
caused a splat with the port spinlock held.
Commit 7c7f9bc986 ("serial: Deassert Transmit Enable on probe in
driver-specific way") erroneously regressed that by spinlocking the
GPIO manipulation again.
Fix by moving uart_rs485_config() (the function manipulating the GPIO)
outside of the spinlocked section and acquiring the spinlock inside of
uart_rs485_config() for the invocation of ->rs485_config() only.
This gets us one step closer to pushing the spinlock down into the
->rs485_config() callbacks which actually need it. (Some callbacks
do not want to be spinlocked because they perform sleepable register
accesses, see e.g. sc16is7xx_config_rs485().)
Stack trace for posterity:
Voluntary context switch within RCU read-side critical section!
WARNING: CPU: 0 PID: 56 at kernel/rcu/tree_plugin.h:318 rcu_note_context_switch
Call trace:
rcu_note_context_switch
__schedule
schedule
schedule_timeout
wait_for_completion_timeout
bcm2835_i2c_xfer
__i2c_transfer
i2c_transfer
i2c_transfer_buffer_flags
regmap_i2c_write
_regmap_raw_write_impl
_regmap_bus_raw_write
_regmap_write
_regmap_update_bits
regmap_update_bits_base
pca953x_gpio_set_value
gpiod_set_raw_value_commit
gpiod_set_value_nocheck
gpiod_set_value_cansleep
uart_rs485_config
uart_add_one_port
pl011_register_port
pl011_probe
Fixes: 7c7f9bc986 ("serial: Deassert Transmit Enable on probe in driver-specific way")
Suggested-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v6.1+
Link: https://lore.kernel.org/r/f3a35967c28b32f3c6432d0aa5936e6a9908282d.1695307688.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 826736a6c7 ]
uart_change_speed() changes more than just speed so rename it to more
generic uart_change_line_settings().
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230309080923.11778-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 8679328eb8 ("serial: Reduce spinlocked portion of uart_rs485_config()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit cce7fc8b29 upstream.
In case the leaf driver wants to use IRQ polling (irq = 0) and
IIR register shows that an interrupt happened in the 8250 hardware
the IRQ data can be NULL. In such a case we need to skip the wake
event as we came to this path from the timer interrupt and quite
likely system is already awake.
Without this fix we have got an Oops:
serial8250: ttyS0 at I/O 0x3f8 (irq = 0, base_baud = 115200) is a 16550A
...
BUG: kernel NULL pointer dereference, address: 0000000000000010
RIP: 0010:serial8250_handle_irq+0x7c/0x240
Call Trace:
? serial8250_handle_irq+0x7c/0x240
? __pfx_serial8250_timeout+0x10/0x10
Fixes: 0ba9e3a13c ("serial: 8250: Add missing wakeup event reporting")
Cc: stable <stable@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20230831222555.614426-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
