USB: fix warning caused by autosuspend counter going negative (195af2cc) · Commits · 戴 / test

This patch (as937) fixes a minor bug in the autosuspend usage-counting code. Each hub's usage counter keeps track of the number of unsuspended children. However the current driver increments the counter after registering a new child, by which time the child may already have been suspended and caused the counter to go negative. The obvious solution is to increment the counter before registering the child. Signed-off-by:

Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@kernel.org> Signed-off-by:

Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/core/hub.c

+6 −4

Original line number	Diff line number	Diff line
		@@ -1335,6 +1335,10 @@ int usb_new_device(struct usb_device *udev)
		udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
		(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));

		/* Increment the parent's count of unsuspended children */
		if (udev->parent)
		usb_autoresume_device(udev->parent);

		/* Register the device. The device driver is responsible
		* for adding the device files to sysfs and for configuring
		* the device.
		@@ -1342,13 +1346,11 @@ int usb_new_device(struct usb_device *udev)
		err = device_add(&udev->dev);
		if (err) {
		dev_err(&udev->dev, "can't device_add, error %d\n", err);
		if (udev->parent)
		usb_autosuspend_device(udev->parent);
		goto fail;
		}

		/* Increment the parent's count of unsuspended children */
		if (udev->parent)
		usb_autoresume_device(udev->parent);

		exit:
		return err;

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