[SERIAL] Fix oops when removing suspended serial port
A serial card might have been removed when the system is resumed.
This results in a suspended port being shut down, which results in
the ports shutdown method being called twice in a row. This causes
BUGs. Avoid this by tracking the suspended state separately from
the initialised state.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index d814bb1..397147a 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -1940,6 +1940,9 @@
if (state->info && state->info->flags & UIF_INITIALIZED) {
const struct uart_ops *ops = port->ops;
+ state->info->flags = (state->info->flags & ~UIF_INITIALIZED)
+ | UIF_SUSPENDED;
+
spin_lock_irq(&port->lock);
ops->stop_tx(port);
ops->set_mctrl(port, 0);
@@ -2006,7 +2009,7 @@
console_start(port->cons);
}
- if (state->info && state->info->flags & UIF_INITIALIZED) {
+ if (state->info && state->info->flags & UIF_SUSPENDED) {
const struct uart_ops *ops = port->ops;
int ret;
@@ -2018,15 +2021,17 @@
ops->set_mctrl(port, port->mctrl);
ops->start_tx(port);
spin_unlock_irq(&port->lock);
+ state->info->flags |= UIF_INITIALIZED;
} else {
/*
* Failed to resume - maybe hardware went away?
* Clear the "initialized" flag so we won't try
* to call the low level drivers shutdown method.
*/
- state->info->flags &= ~UIF_INITIALIZED;
uart_shutdown(state);
}
+
+ state->info->flags &= ~UIF_SUSPENDED;
}
mutex_unlock(&state->mutex);