On Wed, Sep 7, 2016 at 3:47 PM, Rob Herring <robh(a)kernel.org> wrote:
On Tue, Sep 6, 2016 at 1:33 AM, kernel test robot
> FYI, we noticed the following commit:
> commit 761ed4a94582ab291aa24dcbea4e01e8936488c8 ("tty: serial_core: convert
uart_close to use tty_port_close")
> in testcase: boot
> on test machine: qemu-system-x86_64 -enable-kvm -cpu host -smp 2 -m 4G
Is the rootfs used in this test available to help me reproduce?
I reproduced this now. There's a couple of ways to fix this, so I'm
looking for some advice. The problem is tty_port->ops.shutdown()
doesn't get called for a port marked as a console. So interrupts can
still fire and then uart_tx_stopped() called after tty_struct becomes
NULL. I can add a NULL check in uart_tx_stopped to fix that. There are
possibly other spots that need a similar fix. That's going to be
needed anyway as I remove dependencies on tty_struct. The 2nd
possibility is just not marking the tty_port as a console. That seems
wrong, but is what we had before this change. A third option is move
the console handling in tty_port_shutdown into the tty_port drivers.
That seems the wrong direction too. Thoughts?