tty: serial_core: add tty NULL check to uart_tx_stopped
authorRob Herring <robh@kernel.org>
Fri, 9 Sep 2016 22:37:02 +0000 (17:37 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 15 Sep 2016 10:37:09 +0000 (12:37 +0200)
commita727b025f43d7952c0697562f5cecda9f42758aa
tree6c47c8fc223593189222209490600615a0b333f3
parente5e8960236dbff4b49eac1ec7f47b1c912531b62
tty: serial_core: add tty NULL check to uart_tx_stopped

Commit 761ed4a94582 ("tty: serial_core: convert uart_close to use
tty_port_close") created a case where a port used for a console does not
get shutdown on tty closing. Then a call to uart_tx_stopped() segfaults
because the tty is NULL. This could be fixed to restore old behavior,
but we also want to allow tty_ports to work without a tty attached. So
this change to allow a NULL tty_struct is needed either way.

Fixes: 761ed4a94582 ("tty: serial_core: convert uart_close to use tty_port_close")
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
include/linux/serial_core.h