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linuxserial-portkerneldriveruart

What happened my ttyS0 has no irq list in /proc/interrupt

In this system, it blocks(hang) in the following cases:

echo "test" > /dev/ttyS0

cat /dev/ttyS0 #read nothing even scope show the UART data there 

stty -F /dev/ttyS0 115200

If I set serial console in grub, the Linux (CentOS7, Ubuntu18, Redhat7...) can't boot into shell. ( even no getty yet )

Solution

  • because you are not using it.

    update grub to use serial console

    or try:

    cat /dev/ttyS0

    then you will see it on the list.

    For block issue, check you see interrupt on it or not. If no, some problem there.