tree a51e1c4612375a8ada23ecf30fb4ad069a1ef5bd
parent 7ee69102dbc4eea90f46a24f16961226a477dd4c
author Sebastian Andrzej Siewior <bigeasy@linutronix.de> 1515693446 +0100
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1516627256 +0100

serial: core: mark port as initialized after successful IRQ change

setserial changes the IRQ via uart_set_info(). It invokes
uart_shutdown() which free the current used IRQ and clear
TTY_PORT_INITIALIZED. It will then update the IRQ number and invoke
uart_startup() before returning to the caller leaving
TTY_PORT_INITIALIZED cleared.

The next open will crash with
|  list_add double add: new=ffffffff839fcc98, prev=ffffffff839fcc98, next=ffffffff839fcc98.
since the close from the IOCTL won't free the IRQ (and clean the list)
due to the TTY_PORT_INITIALIZED check in uart_shutdown().

There is same pattern in uart_do_autoconfig() and I *think* it also
needs to set TTY_PORT_INITIALIZED there.
Is there a reason why uart_startup() does not set the flag by itself
after the IRQ has been acquired (since it is cleared in uart_shutdown)?

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>