From b64149ca016c25f30b39ac5a8f37cfb9017e19bb Mon Sep 17 00:00:00 2001
From: Lu Baolu <baolu.lu@linux.intel.com>
Date: Thu, 5 Oct 2017 11:21:40 +0300
Subject: [PATCH] usb: xhci: Disable slot even when virt-dev is null
Git-commit: b64149ca016c25f30b39ac5a8f37cfb9017e19bb
References: bsc#1085539
Patch-mainline: v4.15-rc1

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: f9e609b82479 ("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>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/usb/host/xhci-hub.c | 3 +++
 drivers/usb/host/xhci.c     | 4 ----
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index ad89a6d4111b..f0ae9df7cbef 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -612,6 +612,9 @@ 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",
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index e20b2c26a3f1..5cb7c5cd4af5 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3581,11 +3581,7 @@ 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)
-- 
2.13.6