Staging: panel: Prevent double-calling of parport_release - fix oops.

This patch prevents the code from calling parport_release and
parport_unregister_device twice with the same arguments - and thus fixes an oops.

Rationale:
After the first call the parport is already released and the
handle isn't valid anymore and calling parport_release and
parport_unregister_device twice isn't a good idea.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Cc: stable <stable@kernel.org>
Acked-by: Willy Tarreau <w@1wt.eu>

diff --git a/drivers/staging/panel/panel.c b/drivers/staging/panel/panel.c
index 3154ffe59277b2771b4c514f3250a4ed2e1166ba..6fa57beeccb53763485e4269740415d30c491393 100644 (file)
--- a/drivers/staging/panel/panel.c
+++ b/drivers/staging/panel/panel.c
@@ -2277,6 +2277,7 @@ int panel_init(void)
                if (pprt) {
                        parport_release(pprt);
                        parport_unregister_device(pprt);
+                       pprt = NULL;
                }
                parport_unregister_driver(&panel_driver);
                printk(KERN_ERR "Panel driver version " PANEL_VERSION
@@ -2327,6 +2328,7 @@ static void __exit panel_cleanup_module(void)
                /* TODO: free all input signals */
                parport_release(pprt);
                parport_unregister_device(pprt);
+               pprt = NULL;
        }
        parport_unregister_driver(&panel_driver);
 }