[PATCH 1/1] mcb: Do not add the mcb_bus_type to the mcb_bus itself

From: Johannes Thumshirn
Date: Mon Jul 10 2023 - 10:58:54 EST


From: Rodríguez Barbarin, José Javier <JoseJavier.Rodriguez@xxxxxxxxxx>

When allocating a new mcb_bus the bus_type is added to the mcb_bus
itself, causing an issue when calling mcb_bus_add_devices().
This function is not only called for each mcb_device under the
mcb_bus but for the bus itself.

This causes a crash when freeing the ida resources as the bus numbering
gets corrupted due to a wrong cast of structs mcb_bus and mcb_device.

Make the release of the mcb devices and their mcb bus explicit.

Co-developed-by: Jorge Sanjuan Garcia <jorge.sanjuangarcia@xxxxxxxxxx>
Signed-off-by: Jorge Sanjuan Garcia <jorge.sanjuangarcia@xxxxxxxxxx>
Signed-off-by: Javier Rodriguez <josejavier.rodriguez@xxxxxxxxxx>
Signed-off-by: Johannes Thumshirn <jth@xxxxxxxxxx>
---
drivers/mcb/mcb-core.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/mcb/mcb-core.c b/drivers/mcb/mcb-core.c
index 978fdfc19a06..d4535b8aea1d 100644
--- a/drivers/mcb/mcb-core.c
+++ b/drivers/mcb/mcb-core.c
@@ -251,6 +251,12 @@ int mcb_device_register(struct mcb_bus *bus, struct mcb_device *dev)
}
EXPORT_SYMBOL_NS_GPL(mcb_device_register, MCB);

+
+static void mcb_bus_unregister(struct mcb_bus *bus)
+{
+ device_unregister(&bus->dev);
+}
+
static void mcb_free_bus(struct device *dev)
{
struct mcb_bus *bus = to_mcb_bus(dev);
@@ -286,7 +292,6 @@ struct mcb_bus *mcb_alloc_bus(struct device *carrier)

device_initialize(&bus->dev);
bus->dev.parent = carrier;
- bus->dev.bus = &mcb_bus_type;
bus->dev.type = &mcb_carrier_device_type;
bus->dev.release = &mcb_free_bus;

@@ -322,6 +327,7 @@ static void mcb_devices_unregister(struct mcb_bus *bus)
void mcb_release_bus(struct mcb_bus *bus)
{
mcb_devices_unregister(bus);
+ mcb_bus_unregister(bus);
}
EXPORT_SYMBOL_NS_GPL(mcb_release_bus, MCB);

--
2.40.1