Commit 4208d820 authored Oct 05, 2017 by Lu Baolu Committed by Greg Kroah-Hartman Mar 28, 2018

usb: xhci: Disable slot even when virt-dev is null



commit b64149ca016c25f30b39ac5a8f37cfb9017e19bb upstream.

xhci_disable_slot() is a helper for disabling a slot when a device
goes away or recovers from error situations. Currently, it checks
the corespoding virt-dev pointer and returns directly (w/o issuing
disable slot command) if it's null.

This is unnecessary and will cause problems in case where virt-dev
allocation fails and xhci_disable_slot() is called to roll back the
hardware state. Refer to the implementation of xhci_alloc_dev().

This patch removes lines to check virt-dev in xhci_disable_slot().

Fixes: f9e609b8 ("usb: xhci: Add helper function xhci_disable_slot().")
Cc: Guoqing Zhang <guoqing.zhang@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 213b332c

drivers/usb/host/xhci-hub.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -634,6 +634,9 @@ static int xhci_enter_test_mode(struct xhci_hcd *xhci,
		xhci_dbg(xhci, "Disable all slots\n");
		spin_unlock_irqrestore(&xhci->lock, *flags);
		for (i = 1; i <= HCS_MAX_SLOTS(xhci->hcs_params1); i++) {
		if (!xhci->devs[i])
		continue;

		retval = xhci_disable_slot(xhci, NULL, i);
		if (retval)
		xhci_err(xhci, "Failed to disable slot %d, %d. Enter test mode anyway\n",

drivers/usb/host/xhci.c

+0 −4

Original line number	Diff line number	Diff line
		@@ -3571,11 +3571,7 @@ int xhci_disable_slot(struct xhci_hcd xhci, struct xhci_command command,
		unsigned long flags;
		u32 state;
		int ret = 0;
		struct xhci_virt_device *virt_dev;

		virt_dev = xhci->devs[slot_id];
		if (!virt_dev)
		return -EINVAL;
		if (!command)
		command = xhci_alloc_command(xhci, false, false, GFP_KERNEL);
		if (!command)