[lkml]   [2017]   [Aug]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH v4 1/5] usb: xhci: Disable slot even virt-dev is null
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 <>
Signed-off-by: Lu Baolu <>
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 00721e8..6fcb98d 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 b2ff1ff..e69073f 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3567,11 +3567,7 @@ 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)
 \ /
  Last update: 2017-08-17 03:07    [W:0.041 / U:0.640 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site