linux-stable/drivers/tty
Ahung Cheng 494f79bd23 serial: tegra: avoid reg access when clk disabled
This avoids two race conditions from the UART shutdown sequence both
leading to 'Machine check error in AXI2APB' and kernel oops.

One was that the clock was disabled before the DMA was terminated making
it possible for the DMA callbacks to be called after the clock was
disabled. These callbacks could write to the UART registers causing
timeout.

The second was that the clock was disabled before the UART was
completely flagged as closed. This is done after the shutdown is called
and a new write could be started after the clock was disabled.
tegra_uart_start_pio_tx could be called causing timeout.

Given that the baud rate is reset at the end of shutdown sequence, this
fix is to examine the baud rate to avoid register access from both race
conditions.

Besides, terminate the DMA before disabling the clock.

Signed-off-by: Ahung Cheng <ahcheng@nvidia.com>
Signed-off-by: Shardar Mohammed <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-3-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:03 +02:00
..
hvc tty: hvcs: Fix odd use of strlcpy 2019-09-04 12:43:44 +02:00
ipwireless tty: add SPDX identifiers to Kconfig and Makefiles 2019-04-04 18:48:43 +02:00
serdev tty: add SPDX identifiers to Kconfig and Makefiles 2019-04-04 18:48:43 +02:00
serial serial: tegra: avoid reg access when clk disabled 2019-09-05 10:00:03 +02:00
vt vt: Grab console_lock around con_is_bound in show_bind 2019-07-25 13:47:35 +02:00
amiserial.c kill TIOCSERGSTRUCT 2018-10-13 00:50:53 -04:00
cyclades.c cyclades: switch to ->[sg]et_serial() 2018-10-13 00:50:30 -04:00
ehv_bytechan.c tty: Convert to using %pOFn instead of device_node.name 2018-09-18 16:07:25 +02:00
goldfish.c
isicom.c tty/isicom: remove redundant assignment to variable word_count 2019-09-04 12:43:44 +02:00
Kconfig docs: serial: move it to the driver-api 2019-07-15 11:03:03 -03:00
Makefile tty: Add NULL TTY driver 2019-04-16 15:21:34 +02:00
mips_ejtag_fdc.c
moxa.c moxa: switch to ->[sg]et_serial() 2018-10-13 00:50:32 -04:00
moxa.h
mxser.c mxser: switch to ->[sg]et_serial() 2018-10-13 00:50:32 -04:00
mxser.h
n_gsm.c tty: n_gsm: avoid recursive locking with async port hangup 2019-09-04 12:43:56 +02:00
n_hdlc.c tty/n_hdlc: mark expected switch fall-through 2019-02-14 10:49:19 +01:00
n_null.c
n_r3964.c tty: Don't block on IO when ldisc change is pending 2018-12-05 12:16:33 +01:00
n_tracerouter.c
n_tracesink.c
n_tracesink.h
n_tty.c n_tty: check for negative and zero space return from tty_write_room 2019-04-16 15:21:33 +02:00
nozomi.c tty: nozomi: Use dev_get_drvdata 2019-09-04 12:43:44 +02:00
pty.c Revert "tty: pty: Fix race condition between release_one_tty and pty_write" 2019-03-29 15:47:40 +01:00
rocket.c TTY/Serial patches for 5.2-rc1 2019-05-08 10:07:28 -07:00
rocket.h tty: rocket: Remove RCPK_GET_STRUCT ioctl 2019-04-25 11:58:56 +02:00
rocket_int.h
synclink.c tty/synclink: remove ISA support 2019-02-12 08:51:33 +01:00
synclink_gt.c synclink_gt(): fix compat_ioctl() 2018-10-13 00:50:52 -04:00
synclinkmp.c synclink: reduce pointless checks in ->ioctl() 2018-10-13 00:50:43 -04:00
sysrq.c panic: avoid the extra noise dmesg 2019-05-14 19:52:51 -07:00
tty_audit.c audit: join tty records to their syscall 2019-02-07 21:33:54 -05:00
tty_baudrate.c termios, tty/tty_baudrate.c: fix buffer overrun 2018-11-08 03:36:45 -08:00
tty_buffer.c tty: increase the default flip buffer limit to 2*640K 2019-01-30 12:03:58 +01:00
tty_io.c tty: tty_io: fix driver refcount imbalance on error path 2019-05-24 10:09:12 +02:00
tty_ioctl.c move compat handling of tty ioctls to tty_compat_ioctl() 2018-09-14 11:12:17 -04:00
tty_jobctrl.c tty: fix read of tty->pgrp outside of ctrl_lock 2019-03-28 01:28:23 +09:00
tty_ldisc.c proc/sysctl: add shared variables for range check 2019-07-18 17:08:07 -07:00
tty_ldsem.c tty/ldsem, locking/rwsem: Add missing ACQUIRE to read_failed sleep loop 2019-07-25 15:39:24 +02:00
tty_mutex.c
tty_port.c Revert "tty: fix NULL pointer issue when tty_port ops is not set" 2019-04-16 15:21:34 +02:00
ttynull.c tty: Add NULL TTY driver 2019-04-16 15:21:34 +02:00
vcc.c tty: fix up a few remaining files without SPDX identifiers 2019-04-04 18:48:43 +02:00