diff options
| author | Tony Lindgren <tony@atomide.com> | 2023-04-19 14:54:22 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-04-20 13:43:44 +0200 |
| commit | 63f4c34561718a349d321105adab028cbf212d57 (patch) | |
| tree | 6b53a170f76811602e726af7d5aa695dcb9abf74 /drivers/tty | |
| parent | 04e82793f068d2f0ffe62fcea03d007a8cdc16a7 (diff) | |
serial: core: Disable uart_start() on uart_remove_one_port()
While rebinding a uart device in a loop I noticed we may see a tx related
race on uart_remove_one_port():
uart_write from n_tty_write
n_tty_write from file_tty_write.constprop.0
file_tty_write.constprop.0 from vfs_write
vfs_write from ksys_write
ksys_write from ret_fast_syscall
Let's disallow tx on port->UPF_DEAD. This flag gets set before we start
tearing down the port in uart_remove_one_port().
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230419115423.59957-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/serial_core.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 59b62fa2e287..54e82f476a2c 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -135,7 +135,7 @@ static void __uart_start(struct tty_struct *tty) struct uart_state *state = tty->driver_data; struct uart_port *port = state->uart_port; - if (port && !uart_tx_stopped(port)) + if (port && !(port->flags & UPF_DEAD) && !uart_tx_stopped(port)) port->ops->start_tx(port); } |