linux_dsm_epyc7002/drivers/tty/serial
Anssi Hannula 7abab16051 serial: uartps: Fix stuck ISR if RX disabled with non-empty FIFO
If RX is disabled while there are still unprocessed bytes in RX FIFO,
cdns_uart_handle_rx() called from interrupt handler will get stuck in
the receive loop as read bytes will not get removed from the RX FIFO
and CDNS_UART_SR_RXEMPTY bit will never get set.

Avoid the stuck handler by checking first if RX is disabled. port->lock
protects against race with RX-disabling functions.

This HW behavior was mentioned by Nathan Rossi in 43e98facc4a3 ("tty:
xuartps: Fix RX hang, and TX corruption in termios call") which fixed a
similar issue in cdns_uart_set_termios().
The behavior can also be easily verified by e.g. setting
CDNS_UART_CR_RX_DIS at the beginning of cdns_uart_handle_rx() - the
following loop will then get stuck.

Resetting the FIFO using RXRST would not set RXEMPTY either so simply
issuing a reset after RX-disable would not work.

I observe this frequently on a ZynqMP board during heavy RX load at 1M
baudrate when the reader process exits and thus RX gets disabled.

Fixes: 61ec901698 ("tty/serial: add support for Xilinx PS UART")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-19 13:42:07 +01:00
..
8250 serial: 8250_pci: Have ACCES cards that use the four port Pericom PI7C9X7954 chip use the pci_pericom_setup() 2019-02-13 19:48:57 +01:00
cpm_uart mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
jsm tty: serial: jsm: remove redundant pointer ch 2018-07-13 15:36:32 +02:00
21285.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
altera_jtaguart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
altera_uart.c serial: altera: set RRDY flag also without irq 2018-02-28 13:30:09 +01:00
amba-pl010.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
amba-pl011.c serial: set suppress_bind_attrs flag only if builtin 2018-11-09 09:07:17 -08:00
amba-pl011.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
apbuart.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
apbuart.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ar933x_uart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
arc_uart.c serial: arc_uart: Fix out-of-bounds access through DT alias 2018-02-28 15:29:59 +01:00
atmel_serial.c tty/serial: atmel: add ISO7816 support 2018-10-02 13:38:55 -07:00
atmel_serial.h tty/serial: atmel: add ISO7816 support 2018-10-02 13:38:55 -07:00
bcm63xx_uart.c MIPS changes for 4.15 2017-11-15 11:36:08 -08:00
clps711x.c serial: clps711x: Remove board support 2019-01-08 16:55:18 +01:00
digicolor-usart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
dz.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
dz.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
earlycon-arm-semihost.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
earlycon-riscv-sbi.c tty/serial: use uart_console_write in the RISC-V SBL early console 2019-01-23 15:41:50 -08:00
earlycon.c earlycon: Remove hardcoded port->uartclk initialization in of_setup_earlycon 2018-05-14 13:41:05 +02:00
efm32-uart.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
fsl_lpuart.c serial: fsl_lpuart: DMA support for 32-bit variant 2019-01-30 09:31:30 +01:00
icom.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
icom.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
ifx6x60.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
ifx6x60.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
imx.c serial: imx: fix error handling in console_setup 2018-11-27 09:56:20 +01:00
ioc3_serial.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
ioc4_serial.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
ip22zilog.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
ip22zilog.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig serial: Add Tegra Combined UART driver 2019-01-30 09:31:31 +01:00
kgdb_nmi.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
kgdboc.c kgdboc: fix KASAN global-out-of-bounds bug in param_set_kgdboc_var() 2018-12-06 15:59:07 +01:00
lantiq.c serial: lantiq: Do not swap register read/writes 2019-01-08 16:53:36 +01:00
lpc32xx_hs.c tty: serial: lpc32xx_hs: fix missing console boot messages 2019-01-18 11:23:00 +01:00
Makefile serial: Add Tegra Combined UART driver 2019-01-30 09:31:31 +01:00
max310x.c serial: max310x: Correction of the initial setting of the MODE1 bits for various supported ICs. 2019-02-08 10:14:28 +01:00
max3100.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
mcf.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
men_z135_uart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
meson_uart.c tty: serial: meson: if no alias specified use an available id 2019-01-18 11:22:22 +01:00
mpc52xx_uart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
mps2-uart.c serial: mps2-uart: Add parentheses around conditional in mps2_uart_shutdown 2019-01-31 19:34:10 +01:00
mpsc.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
msm_serial.c tty: serial: msm_serial: Add __maybe_unused to suspend/resume callbacks 2018-05-14 13:41:05 +02:00
mux.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
mvebu-uart.c serial: mvebu-uart: initialize over sampling stack register 2018-11-27 09:20:17 +01:00
mxs-auart.c serial: mxs-auart: Fix potential infinite loop 2018-09-18 16:07:24 +02:00
netx-serial.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
omap-serial.c tty: omap-serial: Fix initial on-boot RTS GPIO level 2018-01-09 16:45:17 +01:00
owl-uart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
pch_uart.c pch_uart: remove set but not used variable 'tx_empty' 2018-11-09 09:07:17 -08:00
pic32_uart.c serial: set suppress_bind_attrs flag only if builtin 2018-11-09 09:07:17 -08:00
pic32_uart.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
pmac_zilog.c tty: Use of_node_name_{eq,prefix} for node name comparisons 2018-12-17 16:12:17 +01:00
pmac_zilog.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pnx8xxx_uart.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
pxa.c serial: pxa: Fix an error handling path in 'serial_pxa_probe()' 2018-06-28 21:07:54 +09:00
qcom_geni_serial.c Merge 5.0-rc4 into tty-next 2019-01-28 08:22:00 +01:00
rda-uart.c tty: serial: Add RDA8810PL UART driver 2018-12-31 13:10:01 -08:00
rp2.c treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
sa1100.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
samsung.c tty: serial: samsung: Increase maximum baudrate 2018-12-17 16:16:28 +01:00
samsung.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
sb1250-duart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
sc16is7xx.c sc16is7xx: Use struct_size() in devm_kzalloc() 2019-01-08 16:56:04 +01:00
sccnxp.c serial: sccnxp: Allow to use non-standard baud rates 2018-12-20 16:26:59 +01:00
serial_core.c tty: serial: remove redundant likely annotation 2019-02-19 13:42:07 +01:00
serial_ks8695.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
serial_mctrl_gpio.c gpiolib: Pass array info to get/set array functions 2018-09-13 11:16:54 +02:00
serial_mctrl_gpio.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
serial_txx9.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
serial-tegra.c serial: tegra: fix some spelling mistakes 2018-11-09 08:58:18 -08:00
sh-sci.c Merge 5.0-rc6 into tty-next 2019-02-11 09:26:45 +01:00
sh-sci.h serial: sh-sci: Support for HSCIF RX sampling point adjustment 2018-04-23 10:08:18 +02:00
sirfsoc_uart.c serial: sirf: Fix out-of-bounds access through DT alias 2018-02-28 15:30:00 +01:00
sirfsoc_uart.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
sn_console.c TTY: sn_console: Replace spin_is_locked() with spin_trylock() 2018-10-04 11:06:35 -07:00
sprd_serial.c serial: sprd: Fix the indentation issue 2018-09-18 16:07:24 +02:00
st-asc.c tty: serial: simplify getting .drvdata 2018-04-22 17:29:43 +02:00
stm32-usart.c serial: stm32: fix initialization of RS485 mode 2018-03-15 17:39:43 +01:00
stm32-usart.h serial: stm32: add support for RS485 hardware control mode 2018-03-14 13:35:37 +01:00
suncore.c tty: Use of_node_name_{eq,prefix} for node name comparisons 2018-12-17 16:12:17 +01:00
sunhv.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
sunsab.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
sunsab.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sunsu.c TTY/Serial driver patches for 4.21-rc1 2018-12-28 20:33:54 -08:00
sunzilog.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
sunzilog.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tegra-tcu.c serial: Add Tegra Combined UART driver 2019-01-30 09:31:31 +01:00
timbuart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
timbuart.h tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
uartlite.c serial-uartlite: fix null pointer dereference on pointer port 2018-11-27 09:08:15 +01:00
ucc_uart.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
vr41xx_siu.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
vt8500_serial.c tty: serial: Remove redundant license text 2017-11-08 13:08:12 +01:00
xilinx_uartps.c serial: uartps: Fix stuck ISR if RX disabled with non-empty FIFO 2019-02-19 13:42:07 +01:00
zs.c tty: add SPDX identifiers to all remaining files in drivers/tty/ 2017-11-08 13:08:12 +01:00
zs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00