linux-stable.git/drivers/tty/serial, branch v4.16.7

earlycon: Use a pointer table to fix __earlycon_table stride

2018-05-01T19:47:28+00:00

commit dd709e72cb934eefd44de8d9969097173fbf45dc upstream.

Commit 99492c39f39f ("earlycon: Fix __earlycon_table stride") tried to fix
__earlycon_table stride by forcing the earlycon_id struct alignment to 32
and asking the linker to 32-byte align the __earlycon_table symbol.  This
fix was based on commit 07fca0e57fca92 ("tracing: Properly align linker
defined symbols") which tried a similar fix for the tracing subsystem.

However, this fix doesn't quite work because there is no guarantee that
gcc will place structures packed into an array format.  In fact, gcc 4.9
chooses to 64-byte align these structs by inserting additional padding
between the entries because it has no clue that they are supposed to be in
an array.  If we are unlucky, the linker will assign symbol
"__earlycon_table" to a 32-byte aligned address which does not correspond
to the 64-byte aligned contents of section "__earlycon_table".

To address this same problem, the fix to the tracing system was
subsequently re-implemented using a more robust table of pointers approach
by commits:
 3d56e331b653 ("tracing: Replace syscall_meta_data struct array with pointer array")
 654986462939 ("tracepoints: Fix section alignment using pointer array")
 e4a9ea5ee7c8 ("tracing: Replace trace_event struct array with pointer array")

Let's use this same "array of pointers to structs" approach for
EARLYCON_TABLE.

Fixes: 99492c39f39f ("earlycon: Fix __earlycon_table stride")
Signed-off-by: Daniel Kurtz 
Suggested-by: Aaron Durbin 
Reviewed-by: Rob Herring 
Tested-by: Guenter Roeck 
Reviewed-by: Guenter Roeck 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

serial: mvebu-uart: Fix local flags handling on termios update

2018-05-01T19:47:20+00:00

commit 46c6975a1fd9794ed979565235d24b2f5004e014 upstream.

Commit 68a0db1d7da2 reworked the baud rate selection, but also added
a (not so) subtle change in the way the local flags (c_lflag in the
termios structure) are handled, forcing the new flags to always be the
same as the old ones.

The reason for that particular change is both obscure and undocumented.
It also completely breaks userspace. Something as trivial as getty is
unusable:


	Debian GNU/Linux 9 sy-borg ttyMV0

	sy-borg login: root
	root
	[timeout]

	Debian GNU/Linux 9 sy-borg ttyMV0


which is quite obvious in retrospect: getty cannot get in control of
the echo mode, is stuck in canonical mode, and times out without ever
seeing anything valid. It also begs the question of how this change was
ever tested.

The fix is pretty obvious: stop messing with c_lflag, and the world
will be a happier place.

Cc: stable@vger.kernel.org # 4.15+
Fixes: 68a0db1d7da2 ("serial: mvebu-uart: add function to change baudrate")
Signed-off-by: Marc Zyngier 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: Add Nuvoton NPCM UART

2018-04-08T12:29:49+00:00

commit f597fbce38d230af95384f4a04e0a13a1d0ad45d upstream.

The Nuvoton UART is almost compatible with the 8250 driver when probed
via the 8250_of driver, however it requires some extra configuration
at startup.

Reviewed-by: Rob Herring 
Signed-off-by: Joel Stanley 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

serial: imx: fix bogus dev_err

2018-02-28T12:48:21+00:00

Only one of the two is really required, not both:
* have_rtscts or
* have_rtsgpio

In imx_rs485_config() this is done correctly, so RS485 is working,
just the error message is false.

Signed-off-by: Phil Eichinger 
Reviewed-by: Fabio Estevam 
Fixes: b8f3bff057b0 ("serial: imx: Support common rs485 binding for RTS polarity"
Acked-by: Uwe Kleine-KÃ¶nig 
Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: prevent lockup on full TTY buffers

2018-02-28T12:48:21+00:00

When the TTY buffers fill up to the configured maximum, a system lockup
occurs:

[  598.820128] INFO: rcu_preempt detected stalls on CPUs/tasks:
[  598.825796]  0-...!: (1 GPs behind) idle=5a6/2/0 softirq=1974/1974 fqs=1
[  598.832577]  (detected by 3, t=62517 jiffies, g=296, c=295, q=126)
[  598.838755] Task dump for CPU 0:
[  598.841977] swapper/0       R  running task        0     0      0 0x00000022
[  598.849023] Call trace:
[  598.851476]  __switch_to+0x98/0xb0
[  598.854870]            (null)

This can be prevented by doing a dummy read of the RX data register.

This issue affects both HSCIF and SCIF ports. Reported for R-Car H3 ES2.0;
reproduced and fixed on H3 ES1.1. Probably affects other R-Car platforms
as well.

Reported-by: Yoshihiro Shimoda 
Signed-off-by: Ulrich Hecht 
Reviewed-by: Geert Uytterhoeven 
Cc: stable 
Tested-by: Nguyen Viet Dung 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Add Brainboxes UC-260 4 port serial device

2018-02-28T12:48:21+00:00

Add PCI ids for two variants of Brainboxes UC-260 quad port
PCI serial cards.

Suggested-by: Andy Shevchenko 
Signed-off-by: Nikola Ciprich 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

earlycon: add reg-offset to physical address before mapping

2018-02-28T12:48:21+00:00

It will get the wrong virtual address because port->mapbase is not added
the correct reg-offset yet. We have to update it before earlycon_map()
is called

Signed-off-by: Greentime Hu 
Acked-by: Arnd Bergmann 
Cc: Peter Hurley 
Cc: stable@vger.kernel.org
Fixes: 088da2a17619 ("of: earlycon: Initialize port fields from DT properties")
Acked-by: Rob Herring 
Signed-off-by: Greg Kroah-Hartman

serial: core: mark port as initialized in autoconfig

2018-02-28T12:48:21+00:00

This is a followup on 44117a1d1732 ("serial: core: mark port as
initialized after successful IRQ change").
Nikola has been using autoconfig via setserial and reported a crash
similar to what I fixed in the earlier mentioned commit. Here I do the
same fixup for the autoconfig. I wasn't sure that this is the right
approach. Nikola confirmed that it fixes his crash.

Fixes: b3b576461864 ("tty: serial_core: convert uart_open to use tty_port_open")
Link: http://lkml.kernel.org/r/20180131072000.GD1853@localhost.localdomain
Reported-by: Nikola Ciprich 
Tested-by: Nikola Ciprich 
Cc: 
Signed-off-by: Sebastian Andrzej Siewior 
Tested-by: Nikola Ciprich 
Acked-by: Johan Hovold 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Don't fail on multiport card class

2018-02-28T12:48:21+00:00

Do not fail on multiport cards in serial_pci_is_class_communication().

It restores behaviour for SUNIX multiport cards, that enumerated by
class and have a custom board data.

Moreover it allows users to reenumerate port-by-port from user space.

Fixes: 7d8905d06405 ("serial: 8250_pci: Enable device after we check black list")
Reported-by: Nikola Ciprich 
Signed-off-by: Andy Shevchenko 
Tested-by: Nikola Ciprich 
Signed-off-by: Greg Kroah-Hartman

tty/serial: atmel: add new version check for usart

2018-02-28T12:48:20+00:00

On our at91sam9260 based board the usart0 and usart1 ports report
their versions (ATMEL_US_VERSION) as 0x10302. This version is not
included in the current checks in the driver.

Signed-off-by: Jonas Danielsson 
Acked-by: Richard Genoud 
Acked-by: Nicolas Ferre 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman