Shuah, this driver is getting more and more cryptic and buggy.
Please explain the strategy for serialization before you write patches.
> - Fix attach_store() to check usbip_event_happened() before
> waking up threads.
No, this helps nothing.
> diff --git a/drivers/usb/usbip/vhci_sysfs.c b/drivers/usb/usbip/vhci_sysfs.c
> index c4b4256e5dad3..f0a770adebd97 100644
> --- a/drivers/usb/usbip/vhci_sysfs.c
> +++ b/drivers/usb/usbip/vhci_sysfs.c
> @@ -418,6 +418,15 @@ static ssize_t attach_store(struct device *dev, struct
> device_attribute *attr,
> spin_unlock_irqrestore(&vhci->lock, flags);
> /* end the lock */
>
> + if (usbip_event_happened(&vdev->ud)) {
> + /*
> + * something went wrong - event handler shutting
> + * the connection and doing reset - bail out
> + */
> + dev_err(dev, "Event happended - handler is active\n");
> + return -EAGAIN;
> + }
> +
detach_store() can queue shutdown event as soon as reaching "/* end the lock
*/" line
but attach_store() might be preempted immediately after verifying that
usbip_event_happened() was false (i.e. at this location) in order to wait for
shutdown event posted by detach_store() to be processed.
> wake_up_process(vdev->ud.tcp_rx);
> wake_up_process(vdev->ud.tcp_tx);
>
