usb: Check if port status is equal to RxDetect (bb86cf56) · Commits · 戴 / test

When using USB 3.0 pen drive with the [AMD] FCH USB XHCI Controller [1022:7814], the second hotplugging will experience the USB 3.0 pen drive is recognized as high-speed device. After bisecting the kernel, I found the commit number (USB: Allow USB 3.0 ports to be disabled.) causes the bug. After doing some experiments, the bug can be fixed by avoiding executing the function hub_usb3_port_disable(). Because the port status with [AMD] FCH USB XHCI Controlleris [1022:7814] is already in RxDetect (I tried printing out the port status before setting to Disabled state), it's reasonable to check the port status before really executing hub_usb3_port_disable(). Fixes: (USB: Allow USB 3.0 ports to be disabled.) Signed-off-by:

Gavin Guo <gavin.guo@canonical.com> Acked-by:

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

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/hub.c

+19 −0

Original line number	Original line	Diff line number	Diff line
	@@ -889,6 +889,25 @@ static int hub_usb3_port_disable(struct usb_hub *hub, int port1)
	if (!hub_is_superspeed(hub->hdev))		if (!hub_is_superspeed(hub->hdev))
	return -EINVAL;		return -EINVAL;

			ret = hub_port_status(hub, port1, &portstatus, &portchange);
			if (ret < 0)
			return ret;

			/*
			* USB controller Advanced Micro Devices, Inc. [AMD] FCH USB XHCI
			* Controller [1022:7814] will have spurious result making the following
			* usb 3.0 device hotplugging route to the 2.0 root hub and recognized
			* as high-speed device if we set the usb 3.0 port link state to
			* Disabled. Since it's already in USB_SS_PORT_LS_RX_DETECT state, we
			* check the state here to avoid the bug.
			*/
			if ((portstatus & USB_PORT_STAT_LINK_STATE) ==
			USB_SS_PORT_LS_RX_DETECT) {
			dev_dbg(&hub->ports[port1 - 1]->dev,
			"Not disabling port; link state is RxDetect\n");
			return ret;
			}

	ret = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_SS_DISABLED);		ret = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_SS_DISABLED);
	if (ret)		if (ret)
	return ret;		return ret;

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