From a6b93a908508810c5d51dd9b390283345af6f2d9 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 1 Oct 2006 17:17:40 +0100 Subject: [PATCH] [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 --- drivers/serial/serial_core.c | 9 +++++++-- include/linux/serial_core.h | 1 + 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index d814bb1dcb05..397147a7054f 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -1940,6 +1940,9 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *port) 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 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *port) 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 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *port) 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); diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 86501a3de2ac..f9fdf97506ea 100644 --- a/include/linux/serial_core.h +++ b/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; -- 2.20.1