Alexey Brodkin
6c25cbaff1
serial: 8250_port: Remove dangerous pr_debug() ...
[ Upstream commit 699a11ba7ec869b006623182881f2f1f5b4aea53 ]
With CONFIG_DYNAMIC_DEBUG if dyndbg enables debug output in
8250_port.c deadlock happens inevitably on UART IRQ handling.
That's the problematic execution path:
---------------------------->8------------------------
UART IRQ:
serial8250_interrupt() ->
serial8250_handle_irq(): lock "port->lock" ->
pr_debug() ->
serial8250_console_write(): bump in locked "port->lock".
OR (if above pr_debug() gets removed):
serial8250_tx_chars() ->
pr_debug() ->
serial8250_console_write(): bump in locked "port->lock".
---------------------------->8------------------------
So let's get rid of those not that much useful debug entries.
Discussed problem could be easily reproduced with QEMU for x86_64.
As well as this fix could be mimicked with muting of dynamic debug for
the problematic lines as simple as:
---------------------------->8------------------------
dyndbg="+p; file 8250_port.c line 1756 -p; file 8250_port.c line 1822 -p"
---------------------------->8------------------------
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Phillip Raffeck <phillip.raffeck@fau.de>
Cc: Anton Wuerfel <anton.wuerfel@fau.de>
Cc: "Matwey V. Kornilov" <matwey@sai.msu.ru>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Thor Thayer <tthayer@opensource.altera.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-08 10:26:05 +02:00
serial: 8250_port: Remove dangerous pr_debug()
2017-10-08 10:26:05 +02:00
tty: serial: cpm_uart: Fix module autoload for OF platform driver
2015-10-04 19:09:21 +01:00
tty: serial: jsm_tty: constify uart_ops structures
2016-09-02 15:01:16 +02:00
serial: altera: constify uart_ops structures
2016-09-02 15:01:16 +02:00
serial: altera: constify uart_ops structures
2016-09-02 15:01:16 +02:00
Revert "serial: pl011: add console matching function"
2016-09-30 07:46:35 +02:00
tty: amba-pl011: clean up LCR register offsets
2015-12-13 19:59:48 -08:00
tty: serial: apbuart: Fix module autoload for OF platform driver
2015-10-04 19:09:21 +01:00
tree-wide: replace config_enabled() with IS_ENABLED()
2016-08-04 08:50:07 -04:00
serial/arc: constify uart_ops structures
2016-09-01 21:05:41 +02:00
tty/serial: atmel: fix TX path in atmel_console_write()
2017-04-08 09:30:34 +02:00
serial/bcm63xx_uart: constify uart_ops structures
2016-09-02 15:01:16 +02:00
serial:bfin-uart:Remove 'struct timeval'
2015-12-13 19:59:48 -08:00
serial: clps711x: Changing the compatibility string to match with the smallest supported chip
2016-07-06 17:38:16 +02:00
tty: Replace ASYNC_INITIALIZED bit and update atomically
2016-04-30 09:26:55 -07:00
tty/serial: digicolor: Fix bad usage of IS_ERR_VALUE
2016-02-14 17:39:36 -08:00
tty/serial: mark __init early_smh_setup() static
2016-09-02 15:03:35 +02:00
ACPI: parse SPCR and enable matching console
2016-09-28 17:46:46 +02:00
serial: efm32: Fix parity management in 'efm32_uart_console_get_options()'
2017-06-24 07:11:14 +02:00
serial: etraxfs-uart: Fix crash
2015-11-20 16:19:54 -08:00
tty: serial: fsl_lpuart: Fix Tx DMA edge case
2016-10-27 16:41:56 +02:00
tty: Remove unused SERIAL_DO_RESTART define
2015-12-13 19:59:48 -08:00
serial: ifx6x60: fix use-after-free on module unload
2017-06-14 15:05:54 +02:00
serial: imx: Fix DCD reading
2016-09-27 12:55:27 +02:00
tty: ioc3_serial.c: move assignment out of if () block
2015-05-10 19:04:17 +02:00
tty: ioc4_serial.c: move assignment out of if () block
2015-05-10 19:04:17 +02:00
serial: SERIAL_STM32 should depend on HAS_DMA
2016-10-27 16:00:31 +02:00
serial: kgdb_nmi: Use bool function return values of true/false not 1/0
2015-05-06 22:26:57 +02:00
drivers/tty: make serial/lantic.c driver explicitly non-modular
2015-07-23 18:27:41 -07:00
tty: serial: lpc32xx_hs: fix handling platform_get_irq result
2015-10-04 19:09:21 +01:00
serial: m32r_sio: make it explicitly non-modular
2016-06-25 14:00:06 -07:00
TTY and Serial driver update for 4.7-rc1
2016-05-20 20:57:27 -07:00
serial: max310x: Set IRQF_TRIGGER_FALLING flag when dev.of_node is not NULL
2016-09-15 12:35:49 +02:00
tty: serial: constify uart_ops structures
2016-09-02 15:01:16 +02:00
drivers/tty/serial/mcf.c: fix typo on SERIAL_MCF_CONSOLE
2015-05-06 22:26:59 +02:00
tty: serial: constify uart_ops structures
2016-09-02 15:01:16 +02:00
tty: serial: meson: Implement earlycon support
2016-04-30 09:26:55 -07:00
tty: serial: constify psc_ops structs
2016-02-06 22:31:47 -08:00
serial: mps2-uart: make driver explicitly non-modular
2016-06-25 14:01:57 -07:00
TTY: serial/mpsc, remove unused fields
2016-02-06 22:16:21 -08:00
tty: serial: msm: Fix module autoload
2017-02-26 11:10:51 +01:00
parisc: serial/mux: Convert to uart_console_device instead of open-coded
2015-10-22 15:44:28 +02:00
serial: mvebu-uart: free the IRQ in ->shutdown()
2016-06-25 14:00:06 -07:00
serial: mxs-auart: Fix baudrate calculation
2017-04-08 09:30:34 +02:00
serial: omap: suspend device on probe errors
2017-05-20 14:28:41 +02:00
serial: pch_uart: add terminate entry for dmi_system_id tables
2016-10-27 16:01:31 +02:00
serial: pic32_uart: Fix double free of 'sport->irq_fault_name'.
2016-06-25 13:50:53 -07:00
serial: pic32_uart: Add PIC32 UART driver
2016-05-13 14:01:56 +02:00
TTY: serial, handle platform_get_irq retval properly
2016-06-25 09:01:52 -07:00
serial: pxa: make it explicitly non-modular
2016-06-25 14:00:06 -07:00
serial: samsung: Use right device for DMA-mapping calls
2017-05-20 14:28:41 +02:00
serial: samsung: Register cpufreq notifier only on S3C24xx
2016-08-31 15:39:58 +02:00
sc16is7xx: Drop bogus use of IRQF_ONESHOT
2017-01-09 08:32:22 +01:00
TTY: serial, handle platform_get_irq retval properly
2016-06-25 09:01:52 -07:00
tty: serial_core: fix NULL struct tty pointer access in uart_write_wakeup
2016-10-28 08:13:07 -04:00
serial: Fix ASYNC_* => UPF_* flags misuse
2016-01-28 14:17:42 -08:00
serial: mctrl_gpio: enable API usage only for initialized mctrl_gpios struct
2016-06-25 14:30:42 -07:00
serial: mctrl_gpio: add modem control read routine
2016-06-25 14:30:42 -07:00
serial: sh-sci: Fix late enablement of AUTORTS
2017-06-24 07:11:14 +02:00
serial: sh-sci: Clear (H)SCIF timeout and overrun during reset
2016-06-25 09:09:53 -07:00
serial: sirf: Use generic uart-has-rtscts DT property
2016-04-30 09:26:55 -07:00
serial: sirf: make fifo functions static
2016-06-25 14:01:57 -07:00
drivers/tty: make serial/sn_console.c driver explicitly non-modular
2015-07-23 18:27:41 -07:00
remove lots of IS_ERR_VALUE abuses
2016-05-27 15:26:11 -07:00
serial: st-asc: constify uart_ops structures
2016-09-02 15:01:16 +02:00
serial: stm32: mark symbols static where possible
2016-09-27 12:55:27 +02:00
serial: stm32: Fix comparisons with undefined register
2016-10-27 16:00:31 +02:00
drivers/tty: make serial/suncore.c driver explicitly non-modular
2015-07-23 18:27:41 -07:00
sparc: serial: sunhv: fix a double lock bug
2016-07-27 22:54:52 -07:00
serial/sunsu: Deinline wait_for_xmitr, save 165 bytes
2015-12-13 19:59:48 -08:00
tty: serial: constify uart_ops structures
2016-09-02 15:01:16 +02:00
serial-uartlite: constify uart_ops structures
2016-09-02 15:01:16 +02:00
QE-UART: add "fsl,t1040-ucc-uart" to of_device_id
2016-05-01 13:55:12 -07:00
serial: vt8500_serial: Fix a parameter of find_first_zero_bit.
2016-08-31 15:42:28 +02:00
serial: xuartps: Add new compatible string for ZynqMP
2016-10-27 16:00:32 +02:00
serial: zs: Fix a transmit lockup in console output
2016-02-06 23:13:30 -08:00
6c25cbaff1