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xhci-hub: Handle error condition with xhci_stop_device

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xhci_stop_device() is calling xhci_queue_stop_endpoint() multiple time
and doesn't check return value. xhci_queue_stop_endpoint() can return
error if xhci is already halted or not able to queue command.
xhci_stop_device() waits for stop command completion using
wait_for_completion which wouldn't be interrupted or completed if
queueing of command fails. It results into possible deadlock condition
where usb_disconnect() waits for this udev->lock which is already
acquired by caller of xhci_stop_device() which is set_port_feature().

Fix this issue by handling error condition and making sure that
xhci_stop_device() doesn't wait if queueing of command is failed.

Change-Id: Ica4db17afcd39a7e89fcf985f41760efd2756653
Signed-off-by: Mayank Rana <mrana@codeaurora.org>
This commit is contained in:
Mayank Rana 2016-02-19 15:14:07 -08:00 • committed by David Keitel
parent 2b72760a0a
commit e3020f3887
1 changed files with 14 additions and 3 deletions
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17
drivers/usb/host/xhci-hub.c
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@ -395,11 +395,20 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend)
return -ENOMEM;
}
xhci_queue_stop_endpoint(xhci, command, slot_id, i,
suspend);
ret = xhci_queue_stop_endpoint(xhci, command, slot_id,
i, suspend);
if (ret) {
spin_unlock_irqrestore(&xhci->lock, flags);
goto err_cmd_queue;
}
}
}
xhci_queue_stop_endpoint(xhci, cmd, slot_id, 0, suspend);
ret = xhci_queue_stop_endpoint(xhci, cmd, slot_id, 0, suspend);
if (ret) {
spin_unlock_irqrestore(&xhci->lock, flags);
goto err_cmd_queue;
}
xhci_ring_cmd_db(xhci);
spin_unlock_irqrestore(&xhci->lock, flags);
@ -410,6 +419,8 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend)
xhci_warn(xhci, "Timeout while waiting for stop endpoint command\n");
ret = -ETIME;
}
err_cmd_queue:
xhci_free_command(xhci, cmd);
return ret;
}