[PATCH 3.4 09/92] auxdisplay: ks0108: fix refcount

From: lizf
Date: Mon Apr 18 2016 - 07:19:08 EST


From: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx>

3.4.112-rc1 review patch. If anyone has any objections, please let me know.

------------------


commit bab383de3b84e584b0f09227151020b2a43dc34c upstream.

parport_find_base() will implicitly do parport_get_port() which
increases the refcount. Then parport_register_device() will again
increment the refcount. But while unloading the module we are only
doing parport_unregister_device() decrementing the refcount only once.
We add an parport_put_port() to neutralize the effect of
parport_get_port().

Signed-off-by: Sudip Mukherjee <sudip@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Zefan Li <lizefan@xxxxxxxxxx>
---
drivers/auxdisplay/ks0108.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/auxdisplay/ks0108.c b/drivers/auxdisplay/ks0108.c
index 5b93852..0d75285 100644
--- a/drivers/auxdisplay/ks0108.c
+++ b/drivers/auxdisplay/ks0108.c
@@ -139,6 +139,7 @@ static int __init ks0108_init(void)

ks0108_pardevice = parport_register_device(ks0108_parport, KS0108_NAME,
NULL, NULL, NULL, PARPORT_DEV_EXCL, NULL);
+ parport_put_port(ks0108_parport);
if (ks0108_pardevice == NULL) {
printk(KERN_ERR KS0108_NAME ": ERROR: "
"parport didn't register new device\n");
--
1.9.1