From 7c1eb45a22d76bb99236e7485958f87ef7c449cf Mon Sep 17 00:00:00 2001 From: Haggai Eran Date: Thu, 30 Jul 2015 17:50:14 +0300 Subject: IB/core: lock client data with lists_rwsem An ib_client callback that is called with the lists_rwsem locked only for read is protected from changes to the IB client lists, but not from ib_unregister_device() freeing its client data. This is because ib_unregister_device() will remove the device from the device list with lists_rwsem locked for write, but perform the rest of the cleanup, including the call to remove() without that lock. Mark client data that is undergoing de-registration with a new going_down flag in the client data context. Lock the client data list with lists_rwsem for write in addition to using the spinlock, so that functions calling the callback would be able to lock only lists_rwsem for read and let callbacks sleep. Since ib_unregister_client() now marks the client data context, no need for remove() to search the context again, so pass the client data directly to remove() callbacks. Reviewed-by: Jason Gunthorpe Signed-off-by: Haggai Eran Signed-off-by: Doug Ledford --- drivers/infiniband/core/uverbs_main.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/infiniband/core/uverbs_main.c') diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c index f6eef2da7097..46c92294afa5 100644 --- a/drivers/infiniband/core/uverbs_main.c +++ b/drivers/infiniband/core/uverbs_main.c @@ -128,7 +128,7 @@ static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file, }; static void ib_uverbs_add_one(struct ib_device *device); -static void ib_uverbs_remove_one(struct ib_device *device); +static void ib_uverbs_remove_one(struct ib_device *device, void *client_data); static void ib_uverbs_release_dev(struct kref *ref) { @@ -948,9 +948,9 @@ err: return; } -static void ib_uverbs_remove_one(struct ib_device *device) +static void ib_uverbs_remove_one(struct ib_device *device, void *client_data) { - struct ib_uverbs_device *uverbs_dev = ib_get_client_data(device, &uverbs_client); + struct ib_uverbs_device *uverbs_dev = client_data; if (!uverbs_dev) return; -- cgit v1.2.3