If the parport bus is not yet registered and any device using parallel
port tries to register with the bus we get a stackdump with a message
of Kernel bug.
Reported-by: Fengguang Wu <fengguang...@intel.com>
Tested-by: Ross Zwisler <ross.zwis...@linux.intel.com>
Cc: <sta...@vger.kernel.org> # 4.2+
Signed-off-by: Sudip Mukherjee <sudip.mukher...@codethink.co.uk>
---
We should actually have some deferred probe here. But considering that
you will be closing your trees soon so a quick fix to solve the problem
for now. We will revisit this when we remove the old api (hopefully v4.7).
drivers/parport/share.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/parport/share.c b/drivers/parport/share.c
index 3308427..176b2b6 100644
--- a/drivers/parport/share.c
+++ b/drivers/parport/share.c
@@ -273,6 +273,9 @@ int __parport_register_driver(struct parport_driver *drv,
struct module *owner,
/* using device model */
int ret;
+ if (!parport_bus_type.p)
+ return -EAGAIN;
+
/* initialize common driver fields */
drv->driver.name = drv->name;
drv->driver.bus = &parport_bus_type;
--
1.9.1
