-stable review patch. If anyone has any objections, please let us know.
------------------
From: Russell King <[email protected]>
[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 <[email protected]>
Signed-off-by: maximilian attems <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
---
drivers/serial/serial_core.c | 9 +++++++--
include/linux/serial_core.h | 1 +
2 files changed, 8 insertions(+), 2 deletions(-)
--- linux-2.6.18.1.orig/drivers/serial/serial_core.c
+++ linux-2.6.18.1/drivers/serial/serial_core.c
@@ -1932,6 +1932,9 @@ int uart_suspend_port(struct uart_driver
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);
@@ -1991,7 +1994,7 @@ int uart_resume_port(struct uart_driver
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;
@@ -2003,15 +2006,17 @@ int uart_resume_port(struct uart_driver
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);
--- linux-2.6.18.1.orig/include/linux/serial_core.h
+++ linux-2.6.18.1/include/linux/serial_core.h
@@ -319,6 +319,7 @@ struct uart_info {
#define UIF_CTS_FLOW ((__force uif_t) (1 << 26))
#define UIF_NORMAL_ACTIVE ((__force uif_t) (1 << 29))
#define UIF_INITIALIZED ((__force uif_t) (1 << 31))
+#define UIF_SUSPENDED ((__force uif_t) (1 << 30))
int blocked_open;
--