From 7c7a9bccd2ba9f17e4b588461f140578a0a7b073 Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Tue, 12 Feb 2008 14:38:27 -0800 Subject: [PATCH] IB/cm: Fix infiniband_cm class kobject ref counting Commit 9af57b7a ("IB/cm: Add basic performance counters") introduced a bug in how the reference count for cm_class.subsys.kobj was handled: the path that released a device did a kobject_put() on that kobject, but there was no kobject_get() in the path the handles adding a device. So the reference count ended up too low, which leads to bad things. Fix up and simplify the reference counting to avoid this. (Actually, I introduced the bug when fixing the patch up to match some of Greg's kobject changes, but who's counting) Signed-off-by: Roland Dreier --- drivers/infiniband/core/cm.c | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c index 435e2767a1..b10ade92ef 100644 --- a/drivers/infiniband/core/cm.c +++ b/drivers/infiniband/core/cm.c @@ -3612,18 +3612,12 @@ struct class cm_class = { }; EXPORT_SYMBOL(cm_class); -static void cm_remove_fs_obj(struct kobject *obj) -{ - kobject_put(obj->parent); - kobject_put(obj); -} - static int cm_create_port_fs(struct cm_port *port) { int i, ret; ret = kobject_init_and_add(&port->port_obj, &cm_port_obj_type, - kobject_get(&port->cm_dev->dev_obj), + &port->cm_dev->dev_obj, "%d", port->port_num); if (ret) { kfree(port); @@ -3633,7 +3627,7 @@ static int cm_create_port_fs(struct cm_port *port) for (i = 0; i < CM_COUNTER_GROUPS; i++) { ret = kobject_init_and_add(&port->counter_group[i].obj, &cm_counter_obj_type, - kobject_get(&port->port_obj), + &port->port_obj, "%s", counter_group_names[i]); if (ret) goto error; @@ -3643,8 +3637,8 @@ static int cm_create_port_fs(struct cm_port *port) error: while (i--) - cm_remove_fs_obj(&port->counter_group[i].obj); - cm_remove_fs_obj(&port->port_obj); + kobject_put(&port->counter_group[i].obj); + kobject_put(&port->port_obj); return ret; } @@ -3654,9 +3648,9 @@ static void cm_remove_port_fs(struct cm_port *port) int i; for (i = 0; i < CM_COUNTER_GROUPS; i++) - cm_remove_fs_obj(&port->counter_group[i].obj); + kobject_put(&port->counter_group[i].obj); - cm_remove_fs_obj(&port->port_obj); + kobject_put(&port->port_obj); } static void cm_add_one(struct ib_device *device) @@ -3740,7 +3734,7 @@ error1: ib_unregister_mad_agent(port->mad_agent); cm_remove_port_fs(port); } - cm_remove_fs_obj(&cm_dev->dev_obj); + kobject_put(&cm_dev->dev_obj); } static void cm_remove_one(struct ib_device *device) @@ -3767,7 +3761,7 @@ static void cm_remove_one(struct ib_device *device) ib_unregister_mad_agent(port->mad_agent); cm_remove_port_fs(port); } - cm_remove_fs_obj(&cm_dev->dev_obj); + kobject_put(&cm_dev->dev_obj); } static int __init ib_cm_init(void) -- 2.39.5