When console and printk log are printed at the same time,
they are called through tty driver and console driver concurrently.
In this case, this could lead to potintial issue that
data loss or fifo full.

This issue also occurred with other drivers and has been fixed.
"serial: amba-pl011: lock console writes against interrupts"
 - https://lkml.org/lkml/2012/2/1/495

---
Chnages since v1:
 - locked variable type changed bool from int
 - spin_lock() changed to spin_ock_irqsave()

Jaewon Kim (1):
  tty: serial: samsung: add spin_lock for interrupt and console_write

 drivers/tty/serial/samsung_tty.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

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2.35.1