The patch below does not apply to the 3.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 703df3297fb1950b0aa53e656108eb936d3f21d9 Mon Sep 17 00:00:00 2001 From: Johan Hovold <jhovold@xxxxxxxxx> Date: Mon, 26 May 2014 19:23:42 +0200 Subject: [PATCH] USB: cdc-acm: fix open and suspend race We must not do the usb_autopm_put_interface() before submitting the read urbs or we might end up doing I/O to a suspended device. Fixes: 088c64f81284 ("USB: cdc-acm: re-write read processing") Signed-off-by: Johan Hovold <jhovold@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index c255e77282ad..74df311c8505 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -528,19 +528,15 @@ static int acm_port_activate(struct tty_port *port, struct tty_struct *tty) if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) { dev_err(&acm->control->dev, "%s - usb_submit_urb(ctrl irq) failed\n", __func__); - usb_autopm_put_interface(acm->control); goto error_submit_urb; } acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS; if (acm_set_control(acm, acm->ctrlout) < 0 && (acm->ctrl_caps & USB_CDC_CAP_LINE)) { - usb_autopm_put_interface(acm->control); goto error_set_control; } - usb_autopm_put_interface(acm->control); - /* * Unthrottle device in case the TTY was closed while throttled. */ @@ -552,6 +548,8 @@ static int acm_port_activate(struct tty_port *port, struct tty_struct *tty) if (acm_submit_read_urbs(acm, GFP_KERNEL)) goto error_submit_read_urbs; + usb_autopm_put_interface(acm->control); + mutex_unlock(&acm->mutex); return 0; @@ -562,6 +560,7 @@ error_submit_read_urbs: error_set_control: usb_kill_urb(acm->ctrlurb); error_submit_urb: + usb_autopm_put_interface(acm->control); error_get_interface: disconnected: mutex_unlock(&acm->mutex); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html