If CONFIG_CONSOLE_POLL=y, and CONFIG_SERIAL_CPM=m (hence
CONFIG_SERIAL_CPM_CONSOLE=n):
drivers/tty/serial/cpm_uart/cpm_uart_core.c:1109:12: warning: ‘udbg_cpm_getc’ defined but not used [-Wunused-function]
1109 | static int udbg_cpm_getc(void)
| ^~~~~~~~~~~~~
drivers/tty/serial/cpm_uart/cpm_uart_core.c:1095:13: warning: ‘udbg_cpm_putc’ defined but not used [-Wunused-function]
1095 | static void udbg_cpm_putc(char c)
| ^~~~~~~~~~~~~
Fix this by making the udbg definitions depend on
CONFIG_SERIAL_CPM_CONSOLE, in addition to CONFIG_CONSOLE_POLL.
Fixes: a60526097f ("tty: serial: cpm_uart: Add udbg support for enabling xmon")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20211027075326.3270785-1-geert@linux-m68k.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Data may be stored in DMA RX buffer, when suspending. The data needs
to be pushed to the upper layer. We can't rely on the timeout IRQ (RTOR)
that can't be triggered into low power state. So safely clear DMA request
(DMAR), force the DMA reception routines to push RX buffer content, before
disabling RX DMA. This way, handover to pio mode is safe.
Only call tty_flip_buffer_push() when there is RX data to handle.
Move the locking outside of stm32_usart_receive_chars() to prevent a race
condition, when disabling DMA request upon suspend / pm_runtime_suspend.
Data may be received under IRQ and pushed before
stm32_usart_receive_chars() has pushed older data from DMA rx_buf upon
suspend.
The sequence in suspend routine needs proper locking to avoid this.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-4-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DMA prevents the system to suspend when an UART RX wake-up source is
using DMA. DMA can't suspend while DMA channels are still active.
Terminate DMA transfer at suspend, and restart a new DMA transfer at
resume. Create stm32_usart_start_rx_dma_cyclic function to factorize
dma RX initialization. Move RX DMA code related to wakeup into
stm32_usart_serial_en_wakeup() routine to ease further improvements
on wakeup from low power modes.
Don't enable/disable wakeup on uninitialized port.
There may be data residue in the RX FIFO while suspending. Flush it at
suspend time. Receiver timeout interrupt won't trigger later in low power
mode, so call stm32_usart_receive_chars() in case there's data to handle.
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-3-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The RX DMA channel is kept active forever (from the probe). That prevents
going to low power mode when it is used. This change moves the
DMA configuration and enabling procedures to startup routine to allow
transition to low power mode.
The DMA disabling procedure is implemented in stop_rx routine as this
ops has to stop characters reception, and DMA transation in shutdown.
Clean useless dma_async_tx_descriptor initialization to NULL value.
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211025134229.8456-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xilinx_uartps .start_tx() clears TXEMPTY when enabling TXEMPTY to avoid
any previous TXEVENT event asserting the UART interrupt. This clear
operation is done immediately after filling the TX FIFO.
However, if the bytes inserted by cdns_uart_handle_tx() are consumed by
the UART before the TXEMPTY is cleared, the clear operation eats the new
TXEMPTY event as well, causing cdns_uart_isr() to never receive the
TXEMPTY event. If there are bytes still queued in circbuf, TX will get
stuck as they will never get transferred to FIFO (unless new bytes are
queued to circbuf in which case .start_tx() is called again).
While the racy missed TXEMPTY occurs fairly often with short data
sequences (e.g. write 1 byte), in those cases circbuf is usually empty
so no action on TXEMPTY would have been needed anyway. On the other
hand, longer data sequences make the race much more unlikely as UART
takes longer to consume the TX FIFO. Therefore it is rare for this race
to cause visible issues in general.
Fix the race by clearing the TXEMPTY bit in ISR *before* filling the
FIFO.
The TXEMPTY bit in ISR will only get asserted at the exact moment the
TX FIFO *becomes* empty, so clearing the bit before filling FIFO does
not cause an extra immediate assertion even if the FIFO is initially
empty.
This is hard to reproduce directly on a normal system, but inserting
e.g. udelay(200) after cdns_uart_handle_tx(port), setting 4000000 baud,
and then running "dd if=/dev/zero bs=128 of=/dev/ttyPS0 count=50"
reliably reproduces the issue on my ZynqMP test system unless this fix
is applied.
Fixes: 85baf542d5 ("tty: xuartps: support 64 byte FIFO size")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Link: https://lore.kernel.org/r/20211026102741.2910441-1-anssi.hannula@bitwise.fi
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If CONSOLE_POLL=n, CONFIG_SERIAL_SUNZILOG_CONSOLE=n, and CONFIG_SERIO=m:
drivers/tty/serial/sunzilog.c:1128:13: error: ‘sunzilog_putchar’ defined but not used [-Werror=unused-function]
1128 | static void sunzilog_putchar(struct uart_port *port, int ch)
| ^~~~~~~~~~~~~~~~
Fix this by marking sunzilog_putchar() __maybe_unused.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20211026080426.2444756-1-geert@linux-m68k.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver was updating the port uartclk before setting the new rate in
an attempt to avoid having the clock notifier redundantly update the
divisors.
The set_termios() callback is however called under the termios semaphore
and tty-port mutex so the worker scheduled by the clock notifier will
block in serial8250_update_uartclk() until the uartclk and divisors have
been updated anyway.
Drop the unnecessary swaps and incorrect comment and simply update the
uartclk field if the clock-rate change was successful.
Tested-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211015111422.1027-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch reworks RX support over DMA to improve reliability:
- change dma buffer cyclic configuration by using 2 periods. DMA buffer
data are handled by a flip-flop between the 2 periods in order to avoid
risk of data loss/corruption
- change the size of dma buffer to 4096 to limit overruns
- add rx errors management (breaks, parity, framing and overrun).
When an error occurs on the uart line, the dma request line is masked at
HW level. The SW must 1st clear DMAR (dma request line enable), to
handle the error, then re-enable DMAR to recover. So, any correct data
is taken from the DMA buffer, before handling the error itself. Then
errors are handled from RDR/ISR/FIFO (e.g. in PIO mode). Last, DMA
reception is resumed.
- add a condition on DMA request line in DMA RX routines in order to
switch to PIO mode when no DMA request line is disabled, even if the DMA
channel is still enabled.
When the UART is wakeup source and is configured to use DMA for RX, any
incoming data that wakes up the system isn't correctly received.
At data reception, the irq_handler handles the WUF irq, and then the
data reception over DMA.
As the DMA transfer has been terminated at suspend, and will be restored
by resume callback (which has no yet been called by system), the data
can't be received.
The wake-up data has to be handled in PIO mode while suspend callback
has not been called.
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211020150332.10214-3-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Re-introduce an irq flag condition in usart_receive_chars.
This condition has been deleted by commit 75f4e830fa ("serial: do not
restore interrupt state in sysrq helper").
This code was present to handle threaded case, and has been removed
because it is no more needed in this case. Nevertheless an irq safe lock
is still needed in some cases, when DMA should be stopped to receive errors
or breaks in PIO mode.
This patch is a precursor to the complete rework or stm32 serial driver
DMA implementation.
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20211020150332.10214-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As well known, hvc backend can register its opertions to hvc backend.
the operations contain put_chars(), get_chars() and so on.
Some hvc backend may do dma in its operations. eg, put_chars() of
virtio-console. But in the code of hvc framework, it may pass DMA
incapable memory to put_chars() under a specific configuration, which
is explained in commit c4baad5029(virtio-console: avoid DMA from stack):
1, c[] is on stack,
hvc_console_print():
char c[N_OUTBUF] __ALIGNED__;
cons_ops[index]->put_chars(vtermnos[index], c, i);
2, ch is on stack,
static void hvc_poll_put_char(,,char ch)
{
struct tty_struct *tty = driver->ttys[0];
struct hvc_struct *hp = tty->driver_data;
int n;
do {
n = hp->ops->put_chars(hp->vtermno, &ch, 1);
} while (n <= 0);
}
Commit c4baad5029 is just the fix to avoid DMA from stack memory, which
is passed to virtio-console by hvc framework in above code. But I think
the fix is aggressive, it directly uses kmemdup() to alloc new buffer
from kmalloc area and do memcpy no matter the memory is in kmalloc area
or not. But most importantly, it should better be fixed in the hvc
framework, by changing it to never pass stack memory to the put_chars()
function in the first place. Otherwise, we still face the same issue if
a new hvc backend using dma added in the furture.
In this patch, add 'char cons_outbuf[]' as part of 'struct hvc_struct',
so hp->cons_outbuf is no longer the stack memory, we can use it in above
cases safely. We also add lock to protect cons_outbuf instead of using
the global lock of hvc.
Introduce another array(cons_hvcs[]) for hvc pointers next to the
cons_ops[] and vtermnos[] arrays. With the array, we can easily find
hvc's cons_outbuf and its lock.
With the patch, we can revert the fix c4baad5029.
Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
Signed-off-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Link: https://lore.kernel.org/r/20211015024658.1353987-3-xianting.tian@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
During console setup imx_uart_console_setup() enables clocks, but they
are never disabled when the console is unregistered, this leads to
clk_prepare_enable() being called multiple times without a matching
clk_disable_unprepare() in case of console unregister.
Ensure that clock enable/disable are balanced adding
clk_disable_unprepare() in the console exit callback.
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Link: https://lore.kernel.org/r/20211020192643.476895-3-francesco.dolcini@toradex.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When running ltp testcase(ltp/testcases/kernel/pty/pty04.c) with arm64, there is a soft lockup,
which look like this one:
Workqueue: events_unbound flush_to_ldisc
Call trace:
dump_backtrace+0x0/0x1ec
show_stack+0x24/0x30
dump_stack+0xd0/0x128
panic+0x15c/0x374
watchdog_timer_fn+0x2b8/0x304
__run_hrtimer+0x88/0x2c0
__hrtimer_run_queues+0xa4/0x120
hrtimer_interrupt+0xfc/0x270
arch_timer_handler_phys+0x40/0x50
handle_percpu_devid_irq+0x94/0x220
__handle_domain_irq+0x88/0xf0
gic_handle_irq+0x84/0xfc
el1_irq+0xc8/0x180
slip_unesc+0x80/0x214 [slip]
tty_ldisc_receive_buf+0x64/0x80
tty_port_default_receive_buf+0x50/0x90
flush_to_ldisc+0xbc/0x110
process_one_work+0x1d4/0x4b0
worker_thread+0x180/0x430
kthread+0x11c/0x120
In the testcase pty04, The first process call the write syscall to send
data to the pty master. At the same time, the workqueue will do the
flush_to_ldisc to pop data in a loop until there is no more data left.
When the sender and workqueue running in different core, the sender sends
data fastly in full time which will result in workqueue doing work in loop
for a long time and occuring softlockup in flush_to_ldisc with kernel
configured without preempt. So I add need_resched check and cond_resched
in the flush_to_ldisc loop to avoid it.
Signed-off-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://lore.kernel.org/r/1633961304-24759-1-git-send-email-guanghuifeng@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull libata fixes from Damien Le Moal:
"Two fixes for this cycle:
- Fix a null pointer dereference in ahci-platform driver (from Hai)
- Fix uninitialized variables in pata_legacy driver (from Dan)"
* tag 'libata-5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata:
ata: ahci_platform: fix null-ptr-deref in ahci_platform_enable_regulators()
pata_legacy: fix a couple uninitialized variable bugs
Pull block fixes from Jens Axboe:
"Bigger than usual for this point in time, the majority is fixing some
issues around BDI lifetimes with the move from the request_queue to
the disk in this release. In detail:
- Series on draining fs IO for del_gendisk() (Christoph)
- NVMe pull request via Christoph:
- fix the abort command id (Keith Busch)
- nvme: fix per-namespace chardev deletion (Adam Manzanares)
- brd locking scope fix (Tetsuo)
- BFQ fix (Paolo)"
* tag 'block-5.15-2021-10-17' of git://git.kernel.dk/linux-block:
block, bfq: reset last_bfqq_created on group change
block: warn when putting the final reference on a registered disk
brd: reduce the brd_devices_mutex scope
kyber: avoid q->disk dereferences in trace points
block: keep q_usage_counter in atomic mode after del_gendisk
block: drain file system I/O on del_gendisk
block: split bio_queue_enter from blk_queue_enter
block: factor out a blk_try_enter_queue helper
block: call submit_bio_checks under q_usage_counter
nvme: fix per-namespace chardev deletion
block/rnbd-clt-sysfs: fix a couple uninitialized variable bugs
nvme-pci: Fix abort command id
Pull io_uring fix from Jens Axboe:
"Just a single fix for a wrong condition for grabbing a lock, a
regression in this merge window"
* tag 'io_uring-5.15-2021-10-17' of git://git.kernel.dk/linux-block:
io_uring: fix wrong condition to grab uring lock
Pull virtio fixes from Michael Tsirkin:
"Fixes up some issues in rc5"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost-vdpa: Fix the wrong input in config_cb
VDUSE: fix documentation underline warning
Revert "virtio-blk: Add validation for block size in config space"
vhost_vdpa: unset vq irq before freeing irq
virtio: write back F_VERSION_1 before validate
Pull powerpc fixes from Michael Ellerman:
- Fix a bug where guests on P9 with interrupts passed through could get
stuck in synchronize_irq().
- Fix a bug in KVM on P8 where secondary threads entering a guest would
write outside their allocated stack.
- Fix a bug in KVM on P8 where secondary threads could confuse the host
offline code and cause the guest or host to crash.
Thanks to Cédric Le Goater.
* tag 'powerpc-5.15-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
KVM: PPC: Book3S HV: Make idle_kvm_start_guest() return 0 if it went to guest
KVM: PPC: Book3S HV: Fix stack handling in idle_kvm_start_guest()
powerpc/xive: Discard disabled interrupts in get_irqchip_state()
Pull objtool fixes from Borislav Petkov:
- Update section headers before the respective relocations to not
trigger a safety check in elftoolchain's implementation of libelf
- Do not add garbage data to the .rela.orc_unwind_ip section
* tag 'objtool_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Update section header before relocations
objtool: Check for gelf_update_rel[a] failures
Pull EDAC fix from Borislav Petkov:
- Log the "correct" uncorrectable error count in the armada_xp driver
* tag 'edac_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/armada-xp: Fix output of uncorrectable error counter
Pull perf fix from Borislav Petkov:
- Add Sapphire Rapids to the list of CPUs supporting the SMI count MSR
* tag 'perf_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/msr: Add Sapphire Rapids CPU support
Pull EFI fixes from Borislav Petkov:
"Forwarded from Ard Biesheuvel through the tip tree. Ard will send
stuff directly in the near future.
Low priority fixes but fixes nonetheless:
- update stub diagnostic print that is no longer accurate
- avoid statically allocated buffer for CPER error record decoding
- avoid sleeping on the efi_runtime semaphore when calling the
ResetSystem EFI runtime service"
* tag 'efi-urgent-for-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: Change down_interruptible() in virt_efi_reset_system() to down_trylock()
efi/cper: use stack buffer for error record decoding
efi/libstub: Simplify "Exiting bootservices" message
Pull x86 fixes from Borislav Petkov:
- Do not enable AMD memory encryption in Kconfig by default due to
shortcomings of some platforms, leading to boot failures.
- Mask out invalid bits in the MXCSR for 32-bit kernels again because
Thomas and I don't know how to mask out bits properly. Third time's
the charm.
* tag 'x86_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu: Mask out the invalid MXCSR bits properly
x86/Kconfig: Do not enable AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT automatically
Pull driver core fixes from Greg KH:
"Here are some small driver core fixes for 5.15-rc6, all of which have
been in linux-next for a while with no reported issues.
They include:
- kernfs negative dentry bugfix
- simple pm bus fixes to resolve reported issues"
* tag 'driver-core-5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
drivers: bus: Delete CONFIG_SIMPLE_PM_BUS
drivers: bus: simple-pm-bus: Add support for probing simple bus only devices
driver core: Reject pointless SYNC_STATE_ONLY device links
kernfs: don't create a negative dentry if inactive node exists
Pull char/misc driver fixes from Greg KH:
"Here are some small char/misc driver fixes for 5.15-rc6 for reported
issues that include:
- habanalabs driver fixes
- mei driver fixes and new ids
- fpga new device ids
- MAINTAINER file updates for fpga subsystem
- spi module id table additions and fixes
- fastrpc locking fixes
- nvmem driver fix
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
eeprom: 93xx46: fix MODULE_DEVICE_TABLE
nvmem: Fix shift-out-of-bound (UBSAN) with byte size cells
mei: hbm: drop hbm responses on early shutdown
mei: me: add Ice Lake-N device id.
eeprom: 93xx46: Add SPI device ID table
eeprom: at25: Add SPI ID table
misc: HI6421V600_IRQ should depend on HAS_IOMEM
misc: fastrpc: Add missing lock before accessing find_vma()
cb710: avoid NULL pointer subtraction
misc: gehc: Add SPI ID table
MAINTAINERS: Drop outdated FPGA Manager website
MAINTAINERS: Add Hao and Yilun as maintainers
habanalabs: fix resetting args in wait for CS IOCTL
fpga: ice40-spi: Add SPI device ID table
Pull staging and IIO driver fixes from Greg KH:
"Here are a number of small IIO and staging driver fixes for 5.15-rc6.
They include:
- vc04_services bugfix for reported problem
- r8188eu array underflow fix
- iio driver fixes for a lot of tiny reported issues.
All of these have been in linux-next for a while with no reported
issues"
* tag 'staging-5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: r8188eu: prevent array underflow in rtw_hal_update_ra_mask()
staging: vc04_services: shut up out-of-range warning
iio: light: opt3001: Fixed timeout error when 0 lux
iio: adis16480: fix devices that do not support sleep mode
iio: mtk-auxadc: fix case IIO_CHAN_INFO_PROCESSED
iio: adis16475: fix deadlock on frequency set
iio: ssp_sensors: add more range checking in ssp_parse_dataframe()
iio: ssp_sensors: fix error code in ssp_print_mcu_debug()
iio: adc: ad7793: Fix IRQ flag
iio: adc: ad7780: Fix IRQ flag
iio: adc: ad7192: Add IRQ flag
iio: adc: aspeed: set driver data when adc probe.
iio: adc: rzg2l_adc: add missing clk_disable_unprepare() in rzg2l_adc_pm_runtime_resume()
iio: adc: max1027: Fix the number of max1X31 channels
iio: adc: max1027: Fix wrong shift with 12-bit devices
iio: adc128s052: Fix the error handling path of 'adc128_probe()'
iio: adc: rzg2l_adc: Fix -EBUSY timeout error return
iio: accel: fxls8962af: return IRQ_HANDLED when fifo is flushed
iio: dac: ti-dac5571: fix an error code in probe()
Pull serial driver fix from Greg KH:
"Here is a single 8250 Kconfig fix for 5.15-rc6 that resolves a
regression that showed up in 5.15-rc1. It has been in linux-next for a
while with no reported issues"
* tag 'tty-5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: 8250: allow disabling of Freescale 16550 compile test
Pull USB fixes from Greg KH:
"Here are some small USB fixes that resolve a number of tiny issues.
They include:
- new USB serial driver ids
- xhci driver fixes for a bunch of issues
- musb error path fixes.
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: musb: dsps: Fix the probe error path
xhci: Enable trust tx length quirk for Fresco FL11 USB controller
xhci: Fix command ring pointer corruption while aborting a command
USB: xhci: dbc: fix tty registration race
xhci: add quirk for host controllers that don't update endpoint DCS
xhci: guard accesses to ep_state in xhci_endpoint_reset()
USB: serial: qcserial: add EM9191 QDL support
USB: serial: option: add Quectel EC200S-CN module support
USB: serial: option: add prod. id for Quectel EG91
USB: serial: option: add Telit LE910Cx composition 0x1204
