tree 7eea2b5b397d0b5373ec76035bf924d3885b2489
parent d8d8ffa477831b713ddfa2ad4d0ca545f3b567e5
author Rabin Vincent <rabin.vincent@stericsson.com> 1326797548 +0100
committer Greg Kroah-Hartman <gregkh@suse.de> 1327450195 -0800

serial: amba-pl011: lock console writes against interrupts

Protect against pl011_console_write() and the interrupt for
the console UART running concurrently on different CPUs.

Otherwise the console_write could spin for a long time
waiting for the UART to become not busy, while the other
CPU continuously services UART interrupts and keeps the
UART busy.

The checks for sysrq and oops_in_progress are taken
from 8250.c.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Reviewed-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Reviewed-by: Bibek Basu <bibek.basu@stericsson.com>
Reviewed-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>