n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.8.1 states that XON/XOFF characters
shall be used instead of Fcon/Fcoff command in advanced option mode to
handle flow control. Chapter 5.4.8.2 describes how XON/XOFF characters
shall be handled. Basic option mode only used Fcon/Fcoff commands and no
XON/XOFF characters. These are treated as data bytes here.
The current implementation uses the gsm_mux field 'constipated' to handle
flow control from the remote peer and the gsm_dlci field 'constipated' to
handle flow control from each DLCI. The later is unrelated to this patch.
The gsm_mux field is correctly set for Fcon/Fcoff commands in
gsm_control_message(). However, the same is not true for XON/XOFF
characters in gsm1_receive().
Disable software flow control handling in the tty to allow explicit
handling by n_gsm.
Add the missing handling in advanced option mode for gsm_mux in
gsm1_receive() to comply with the standard.
This patch depends on the following commit:
Commit 8838b2af23 ("tty: n_gsm: fix SW flow control encoding/handling")
Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220422071025.5490-3-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.6.3.7 states that the Modem Status
Command (MSC) shall only be used if the basic option was chosen.
The current implementation uses MSC frames even if advanced option was
chosen to inform the peer about modem line state updates. A standard
conform peer may choose to discard these frames in advanced option mode.
Furthermore, gsmtty_modem_update() is not part of the 'tty_operations'
functions despite its name.
Rename gsmtty_modem_update() to gsm_modem_update() to clarify this. Split
its function into gsm_modem_upd_via_data() and gsm_modem_upd_via_msc()
depending on the encoding and adaption. Introduce gsm_dlci_modem_output()
as adaption of gsm_dlci_data_output() to encode and queue empty frames in
advanced option mode. Use it in gsm_modem_upd_via_data().
gsm_modem_upd_via_msc() is based on the initial gsmtty_modem_update()
function which used only MSC frames to update modem states.
Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220422071025.5490-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Dynamic virtual tty registration was introduced to allow the user to handle
these cases with uevent rules. The following commits relate to this:
Commit 5b87686e32 ("tty: n_gsm: Modify gsmtty driver register method when config requester")
Commit 0b91b53323 ("tty: n_gsm: Save dlci address open status when config requester")
Commit 46292622ad ("tty: n_gsm: clean up indenting in gsm_queue()")
However, the following behavior can be seen with this implementation:
- n_gsm ldisc is activated via ioctl
- all configuration parameters are set to their default value (initiator=0)
- the mux gets activated and attached and gsmtty0 is being registered in
in gsm_dlci_open() after DLCI 0 was established (DLCI 0 is the control
channel)
- the user configures n_gsm via ioctl GSMIOC_SETCONF as initiator
- this re-attaches the n_gsm mux
- no new gsmtty devices are registered in gsmld_attach_gsm() because the
mux is already active
- the initiator side registered only the control channel as gsmtty0
(which should never happen) and no user channel tty
The commits above make it impossible to operate the initiator side as no
user channel tty is or will be available.
On the other hand, this behavior will make it also impossible to allow DLCI
parameter negotiation on responder side in the future. The responder side
first needs to provide a device for the application before the application
can set its parameters of the associated DLCI via ioctl.
Note that the user application is still able to detect a link establishment
without relaying to uevent by waiting for DTR open on responder side. This
is the same behavior as on a physical serial interface. And on initiator
side a tty hangup can be detected if a link establishment request failed.
Revert the commits above completely to always register all user channels
and no control channel after mux attachment. No other changes are made.
Fixes: 5b87686e32 ("tty: n_gsm: Modify gsmtty driver register method when config requester")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220422071025.5490-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Do not set timeout to twice the approximate amount of time to send the
entire FIFO if CTS is enabled. If the caller requested no timeout, e.g.
when userspace program called tcdrain(), then wait without any timeout.
Premature return from tcdrain() was observed on imx based system which
has 32 character long transmitter FIFO with hardware CTS handling.
Simple userspace application that reproduces problem has to:
* Open tty device, enable hardware flow control (CRTSCTS)
* Write data, e.g. 26 bytes
* Call tcdrain() to wait for the transmitter
* Close tty device
The other side of serial connection has to:
* Receive some data, e.g. 10 bytes
* Set RTS output (CTS input from sender perspective) inactive for
at least twice the port timeout
* Try to receive remaining data
Without this patch, userspace application will finish without any error
while the other side of connection will never receive remaining data.
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220228054911.1420221-1-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Note: I am using a small test app + driver located at [0] for the
problem description. serco is a driver whose write function dispatches
to the serial controller. sertest is a user-mode app that writes n bytes
to the serial console using the serco driver.
While investigating a bug in the RHEL kernel, I noticed that the serial
console throughput is way below the configured speed of 115200 bps in
a HP Proliant DL380 Gen9. I was expecting something above 10KB/s, but
I got 2.5KB/s.
$ time ./sertest -n 2500 /tmp/serco
real 0m0.997s
user 0m0.000s
sys 0m0.997s
With the help of the function tracer, I then noticed the serial
controller was taking around 410us seconds to dispatch one single byte:
$ trace-cmd record -p function_graph -g serial8250_console_write \
./sertest -n 1 /tmp/serco
$ trace-cmd report
| serial8250_console_write() {
0.384 us | _raw_spin_lock_irqsave();
1.836 us | io_serial_in();
1.667 us | io_serial_out();
| uart_console_write() {
| serial8250_console_putchar() {
| wait_for_xmitr() {
1.870 us | io_serial_in();
2.238 us | }
1.737 us | io_serial_out();
4.318 us | }
4.675 us | }
| wait_for_xmitr() {
1.635 us | io_serial_in();
| __const_udelay() {
1.125 us | delay_tsc();
1.429 us | }
...
...
...
1.683 us | io_serial_in();
| __const_udelay() {
1.248 us | delay_tsc();
1.486 us | }
1.671 us | io_serial_in();
411.342 us | }
In another machine, I measured a throughput of 11.5KB/s, with the serial
controller taking between 80-90us to send each byte. That matches the
expected throughput for a configuration of 115200 bps.
This patch changes the serial8250_console_write to use the 16550 fifo
if available. In my benchmarks I got around 25% improvement in the slow
machine, and no performance penalty in the fast machine.
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Link: https://lore.kernel.org/r/20220411174841.34936-2-wander@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a deadlock in sa1100_set_termios(), which is shown
below:
(Thread 1) | (Thread 2)
| sa1100_enable_ms()
sa1100_set_termios() | mod_timer()
spin_lock_irqsave() //(1) | (wait a time)
... | sa1100_timeout()
del_timer_sync() | spin_lock_irqsave() //(2)
(wait timer to stop) | ...
We hold sport->port.lock in position (1) of thread 1 and
use del_timer_sync() to wait timer to stop, but timer handler
also need sport->port.lock in position (2) of thread 2. As a result,
sa1100_set_termios() will block forever.
This patch moves del_timer_sync() before spin_lock_irqsave()
in order to prevent the deadlock.
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Link: https://lore.kernel.org/r/20220417111626.7802-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some more serial drivers can be compile-tested under certain
circumstances (when building a specific architecture). So allow for
that.
This reduces the need of zillion mach/subarch-specific configs. And
since the 0day bot has only allmodconfig's for some archs, this
increases build coverage there too.
Note that cpm needs a minor update in the header, so that it drags in
at least some defines (CPM2 ones).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pic32_uart contains this:
#ifdef CONFIG_SERIAL_PIC32_CONSOLE
...
console_initcall(pic32_console_init);
...
core_initcall(pic32_late_console_init);
...
#endif
...
arch_initcall(pic32_uart_init);
When the driver is built as module, all three above become
module_init(). So if SERIAL_PIC32_CONSOLE is set while SERIAL_PIC32=m,
it results in the following build error:
In file included from include/linux/device/driver.h:21,
from include/linux/device.h:32,
from include/linux/platform_device.h:13,
from drivers/tty/serial/pic32_uart.c:12:
include/linux/module.h:131:49: error: redefinition of '__inittest'
So make sure SERIAL_PIC32_CONSOLE can be set only when SERIAL_PIC32=y --
similar as for other drivers.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421101708.5640-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use list_for_each_entry() helper instead of explicit combo of
list_for_each() and list_entry().
Note that pos is used as a reference point in list_add_tail() in
icom_alloc_adapter(). This functionality remains as with an empty list,
cur_adapter_entry->icom_adapter_entry is still the list head.
This simplifies the code a bit.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a lot of sparse warnings:
.../icom.c:228:30: warning: cast from restricted __le16
.../icom.c:232:66: warning: incorrect type in assignment (different base types)
.../icom.c:232:66: expected unsigned int [usertype] leBuffer
.../icom.c:232:66: got restricted __le32 [usertype]
.../icom.c:237:30: warning: cast from restricted __le16
...
.../icom.c:1228:22: warning: cast from restricted __le16
And they are correct. So sort them all out by using proper __leXX and
uXX types and the right direction of conversion: le16_to_cpu() instead
of cpu_to_le16(), where appropriate.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In icom, there is an ICOM_PORT macro to perform upcasts from struct
uart_port to struct icom_port. It's not completely safe and it works
only because the first member of icom_port is uart_port. Nowadays, we
use container_of for such an upcast instead.
So introduce a helper (to_icom_port()) with container_of in it and
convert all the ICOM_PORT users to the new helper. Apart from the code
and type safety, it's also clear what icom_port (the variable) is.
Unlike with the old ICOM_PORT (the macro with the cast).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To move towards a more consistent behaviour between genpd and the runtime
PM core, let's start by converting genpd's time-accounting from ktime_get()
into ktime_get_mono_fast_ns().
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ap_init_early function is defined a global but has no declaration,
so it produces a warning:
arch/arm/mach-versatile/integrator_ap.c:148:13: warning: no previous prototype for 'ap_init_early' [-Wmissing-prototypes
The function could be made 'static' but since it's empty, we can
just remove it.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Kees writes:
lkdtm updates for next
Christophe Leroy (1):
lkdtm/bugs: Don't expect thread termination without CONFIG_UBSAN_TRAP
Jiasheng Jiang (1):
lkdtm/bugs: Check for the NULL pointer after calling kmalloc
Kees Cook (4):
lkdtm/heap: Note conditions for SLAB_LINEAR_OVERFLOW
lkdtm/usercopy: Expand size of "out of frame" object
lkdtm: Move crashtype definitions into each category
lkdtm: Add CFI_BACKWARD to test ROP mitigations
* tag 'lkdtm-next' of https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
lkdtm: Add CFI_BACKWARD to test ROP mitigations
lkdtm: Move crashtype definitions into each category
lkdtm/bugs: Don't expect thread termination without CONFIG_UBSAN_TRAP
lkdtm/usercopy: Expand size of "out of frame" object
lkdtm/heap: Note conditions for SLAB_LINEAR_OVERFLOW
lkdtm/bugs: Check for the NULL pointer after calling kmalloc
Georgi writes:
interconnect fixes for v5.18
This contains a fix for a reported issue on sc7180 platforms, where
one of the resources has been incorrectly modelled as both clock and
interconnect, which is causing a crash when both frameworks try to
manage it. Fix the same issue also on another platform that appears
to be affected by the same.
- interconnect: qcom: sc7180: Drop IP0 interconnects
- interconnect: qcom: sdx55: Drop IP0 interconnects
Signed-off-by: Georgi Djakov <djakov@kernel.org>
* tag 'icc-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/djakov/icc:
interconnect: qcom: sdx55: Drop IP0 interconnects
interconnect: qcom: sc7180: Drop IP0 interconnects
This patch fixes spurious EEXIST errors.
Extend d2df92e98a ("netfilter: nft_set_rbtree: handle element
re-addition after deletion") to deal with elements with same end flags
in the same transation.
Reset the overlap flag as described by 7c84d41416 ("netfilter:
nft_set_rbtree: Detect partial overlaps on insertion").
Fixes: 7c84d41416 ("netfilter: nft_set_rbtree: Detect partial overlaps on insertion")
Fixes: d2df92e98a ("netfilter: nft_set_rbtree: handle element re-addition after deletion")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Manivannan writes:
MHI fixes for v5.18
Couple of patches fixing the hibernation issue seen on MHI endpoint devices like
SDX65 modems:
- During hibernation, the host puts the device into D3cold after thaw() stage.
But at that time, the device would be in M0 state. So the device emits a
warning (not visible to the host but to device firmware only) stating invalid
transition. This is fixed by adding a poweroff() callback that puts the device
into M3 before D3cold.
- There is a possibility that the recovery worker might be running while trying
to powerdown the device. So flush the recovery worker before that.
* tag 'mhi-fixes-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mani/mhi:
bus: mhi: host: pci_generic: Flush recovery worker during freeze
bus: mhi: host: pci_generic: Add missing poweroff() PM callback
