diff options
| author | Johan Hovold <johan@kernel.org> | 2020-09-09 16:31:00 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-09-16 13:22:10 +0200 |
| commit | fe88c6489264eaea23570dfdf03e1d3f5f47f423 (patch) | |
| tree | 3a718fd52c2788836eda9320438748bfa1437516 /drivers | |
| parent | Linux 5.9-rc3 (diff) | |
| download | linux-fe88c6489264eaea23570dfdf03e1d3f5f47f423.tar.xz linux-fe88c6489264eaea23570dfdf03e1d3f5f47f423.zip | |
serial: core: fix port-lock initialisation
Commit f743061a85f5 ("serial: core: Initialise spin lock before use in
uart_configure_port()") tried to work around a breakage introduced by
commit a3cb39d258ef ("serial: core: Allow detach and attach serial
device for console") by adding a second initialisation of the port lock
when registering the port.
As reported by the build robots [1], this doesn't really solve the
regression introduced by the console-detach changes and also adds a
second redundant initialisation of the lock for normal ports.
Start cleaning up this mess by removing the redundant initialisation and
making sure that the port lock is again initialised once-only for ports
that aren't already in use as a console.
[1] https://lore.kernel.org/r/20200802054852.GR23458@shao2-debian
Fixes: f743061a85f5 ("serial: core: Initialise spin lock before use in uart_configure_port()")
Fixes: a3cb39d258ef ("serial: core: Allow detach and attach serial device for console")
Cc: stable <stable@vger.kernel.org> # 5.7
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200909143101.15389-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/tty/serial/serial_core.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index f797c971cd82..53b79e1fcbc8 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -2379,13 +2379,6 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state, uart_change_pm(state, UART_PM_STATE_ON); /* - * If this driver supports console, and it hasn't been - * successfully registered yet, initialise spin lock for it. - */ - if (port->cons && !(port->cons->flags & CON_ENABLED)) - __uart_port_spin_lock_init(port); - - /* * Ensure that the modem control lines are de-activated. * keep the DTR setting that is set in uart_set_options() * We probably don't need a spinlock around this, but @@ -2900,7 +2893,12 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport) goto out; } - uart_port_spin_lock_init(uport); + /* + * If this port is in use as a console then the spinlock is already + * initialised. + */ + if (!uart_console_enabled(uport)) + __uart_port_spin_lock_init(uport); if (uport->cons && uport->dev) of_console_check(uport->dev->of_node, uport->cons->name, uport->line); |