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authorJim Lin <jilin@nvidia.com>2016-08-16 10:18:05 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-08-16 10:42:47 +0300
commit88716a93766b8f095cdef37a8e8f2c93aa233b21 (patch)
tree84526c20f326aff248ea30ab49c720cf67051fa0
parent0d2daaded82565f807a4435d678343f437b8b848 (diff)
downloadlinux-88716a93766b8f095cdef37a8e8f2c93aa233b21.tar.xz
usb: xhci: Fix panic if disconnect
After a device is disconnected, xhci_stop_device() will be invoked in xhci_bus_suspend(). Also the "disconnect" IRQ will have ISR to invoke xhci_free_virt_device() in this sequence. xhci_irq -> xhci_handle_event -> handle_cmd_completion -> xhci_handle_cmd_disable_slot -> xhci_free_virt_device If xhci->devs[slot_id] has been assigned to NULL in xhci_free_virt_device(), then virt_dev->eps[i].ring in xhci_stop_device() may point to an invlid address to cause kernel panic. virt_dev = xhci->devs[slot_id]; : if (virt_dev->eps[i].ring && virt_dev->eps[i].ring->dequeue) [] Unable to handle kernel paging request at virtual address 00001a68 [] pgd=ffffffc001430000 [] [00001a68] *pgd=000000013c807003, *pud=000000013c807003, *pmd=000000013c808003, *pte=0000000000000000 [] Internal error: Oops: 96000006 [#1] PREEMPT SMP [] CPU: 0 PID: 39 Comm: kworker/0:1 Tainted: G U [] Workqueue: pm pm_runtime_work [] task: ffffffc0bc0e0bc0 ti: ffffffc0bc0ec000 task.ti: ffffffc0bc0ec000 [] PC is at xhci_stop_device.constprop.11+0xb4/0x1a4 This issue is found when running with realtek ethernet device (0bda:8153). Signed-off-by: Jim Lin <jilin@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/usb/host/xhci-hub.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index d61fcc48099e..730b9fd26685 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -386,6 +386,9 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend)
ret = 0;
virt_dev = xhci->devs[slot_id];
+ if (!virt_dev)
+ return -ENODEV;
+
cmd = xhci_alloc_command(xhci, false, true, GFP_NOIO);
if (!cmd) {
xhci_dbg(xhci, "Couldn't allocate command structure.\n");