Re: [PATCH v2 5/8] usb: mausb_host: Introduce PAL processing

From: Oliver Neukum
Date: Wed Feb 26 2020 - 07:35:43 EST


Am Mittwoch, den 26.02.2020, 09:58 +0000 schrieb Vladimir Stankovic

+int mausb_enqueue_event_from_user(u8 madev_addr, u16 num_of_events,
+ u16 num_of_completed)
+{
+ unsigned long flags;
+ struct mausb_device *dev;
+
+ spin_lock_irqsave(&mss.lock, flags);

You save the flags.

+ dev = mausb_get_dev_from_addr_unsafe(madev_addr);
+
+ if (!dev) {
+ spin_unlock_irqrestore(&mss.lock, flags);
+ return -EINVAL;
+ }
+
+ spin_lock_irqsave(&dev->num_of_user_events_lock, flags);

You overwrite the flags.

+ dev->num_of_user_events += num_of_events;
+ dev->num_of_completed_events += num_of_completed;
+ spin_unlock_irqrestore(&dev->num_of_user_events_lock, flags);

Your restore the flags.

+ queue_work(dev->workq, &dev->work);
+ spin_unlock_irqrestore(&mss.lock, flags);

You restore the overwritten flags.

This cannot be right.

Regards
Oliver