Commit 18a77b5d authored Nov 04, 2009 by Henry Gebhardt Committed by Greg Kroah-Hartman Nov 17, 2009

USB: cdc_acm: Fix race condition when opening tty



If acm_rx_tasklet() gets called before tty_port_block_til_ready()
returns, then bulk IN urbs may not be sent. This fixes it.

Signed-off-by: Henry Gebhardt <gebhardt@astro.uni-tuebingen.de>
Acked-by: Oliver Neukum <oliver@neukum.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent a1f17a87

drivers/usb/class/cdc-acm.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -609,9 +609,9 @@ static int acm_tty_open(struct tty_struct tty, struct file filp)

		acm->throttle = 0;

		tasklet_schedule(&acm->urb_task);
		set_bit(ASYNCB_INITIALIZED, &acm->port.flags);
		rv = tty_port_block_til_ready(&acm->port, tty, filp);
		tasklet_schedule(&acm->urb_task);
		done:
		mutex_unlock(&acm->mutex);
		err_out: