xhci: init command timeout timer earlier to avoid deleting it uninitialized

Don't check if timer is running with a timer_pending() before
deleting it with del_timer_sync(), this defies the whole point of
the sync part and can cause a possible race.

Instead we just want to make sure the timer is initialized early enough
before we have a chance to delete it.

Cc: <stable@vger.kernel.org>
Reported-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 8497fb8f61933d24916f5bece56529d55b1b68ad..41f841fa6c4de6a57edb702c2875e4351a4cbff8 100644 (file)
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1792,8 +1792,7 @@ void xhci_mem_cleanup(struct xhci_hcd *xhci)
        int size;
        int i, j, num_ports;
 
-       if (timer_pending(&xhci->cmd_timer))
-               del_timer_sync(&xhci->cmd_timer);
+       del_timer_sync(&xhci->cmd_timer);
 
        /* Free the Event Ring Segment Table and the actual Event Ring */
        size = sizeof(struct xhci_erst_entry)*(xhci->erst.num_entries);
@@ -2321,6 +2320,10 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 
        INIT_LIST_HEAD(&xhci->cmd_list);
 
+       /* init command timeout timer */
+       setup_timer(&xhci->cmd_timer, xhci_handle_command_timeout,
+                   (unsigned long)xhci);
+
        page_size = readl(&xhci->op_regs->page_size);
        xhci_dbg_trace(xhci, trace_xhci_dbg_init,
                        "Supported page size register = 0x%x", page_size);
@@ -2505,10 +2508,6 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
                        "Wrote ERST address to ir_set 0.");
        xhci_print_ir_set(xhci, 0);
 
-       /* init command timeout timer */
-       setup_timer(&xhci->cmd_timer, xhci_handle_command_timeout,
-                   (unsigned long)xhci);
-
        /*
         * XXX: Might need to set the Interrupter Moderation Register to
         * something other than the default (~1ms minimum between interrupts).