diff options
author | Jack Morgenstein <jackm@mellanox.co.il> | 2006-08-03 13:56:42 -0400 |
---|---|---|
committer | Roland Dreier <rolandd@cisco.com> | 2006-08-03 13:56:42 -0400 |
commit | fd60ae404f104f12369e654af9cf03b1f1047661 (patch) | |
tree | 81fcc683f41936597e62cdba254b89ab569e5526 | |
parent | 8ddc7c5326064434048ec1ecfe57659e08345cc1 (diff) |
IB/uverbs: Avoid a crash on device hot remove
Wait until all users have closed their device context before allowing
device unregistration to complete. This prevents a crash caused by
referring to stale data structures.
A better solution would be to have a way to revoke contexts rather
than waiting for userspace to close the context, but that's a much
bigger change that will have to wait. For now let's at least avoid
the crash.
Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
-rw-r--r-- | drivers/infiniband/core/uverbs.h | 2 | ||||
-rw-r--r-- | drivers/infiniband/core/uverbs_main.c | 8 |
2 files changed, 9 insertions, 1 deletions
diff --git a/drivers/infiniband/core/uverbs.h b/drivers/infiniband/core/uverbs.h index bb9bee56a824..102a59c033ff 100644 --- a/drivers/infiniband/core/uverbs.h +++ b/drivers/infiniband/core/uverbs.h | |||
@@ -42,6 +42,7 @@ | |||
42 | #include <linux/kref.h> | 42 | #include <linux/kref.h> |
43 | #include <linux/idr.h> | 43 | #include <linux/idr.h> |
44 | #include <linux/mutex.h> | 44 | #include <linux/mutex.h> |
45 | #include <linux/completion.h> | ||
45 | 46 | ||
46 | #include <rdma/ib_verbs.h> | 47 | #include <rdma/ib_verbs.h> |
47 | #include <rdma/ib_user_verbs.h> | 48 | #include <rdma/ib_user_verbs.h> |
@@ -69,6 +70,7 @@ | |||
69 | 70 | ||
70 | struct ib_uverbs_device { | 71 | struct ib_uverbs_device { |
71 | struct kref ref; | 72 | struct kref ref; |
73 | struct completion comp; | ||
72 | int devnum; | 74 | int devnum; |
73 | struct cdev *dev; | 75 | struct cdev *dev; |
74 | struct class_device *class_dev; | 76 | struct class_device *class_dev; |
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c index e725cccc7cde..4e16314e8e6d 100644 --- a/drivers/infiniband/core/uverbs_main.c +++ b/drivers/infiniband/core/uverbs_main.c | |||
@@ -122,7 +122,7 @@ static void ib_uverbs_release_dev(struct kref *ref) | |||
122 | struct ib_uverbs_device *dev = | 122 | struct ib_uverbs_device *dev = |
123 | container_of(ref, struct ib_uverbs_device, ref); | 123 | container_of(ref, struct ib_uverbs_device, ref); |
124 | 124 | ||
125 | kfree(dev); | 125 | complete(&dev->comp); |
126 | } | 126 | } |
127 | 127 | ||
128 | void ib_uverbs_release_ucq(struct ib_uverbs_file *file, | 128 | void ib_uverbs_release_ucq(struct ib_uverbs_file *file, |
@@ -740,6 +740,7 @@ static void ib_uverbs_add_one(struct ib_device *device) | |||
740 | return; | 740 | return; |
741 | 741 | ||
742 | kref_init(&uverbs_dev->ref); | 742 | kref_init(&uverbs_dev->ref); |
743 | init_completion(&uverbs_dev->comp); | ||
743 | 744 | ||
744 | spin_lock(&map_lock); | 745 | spin_lock(&map_lock); |
745 | uverbs_dev->devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES); | 746 | uverbs_dev->devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES); |
@@ -793,6 +794,8 @@ err_cdev: | |||
793 | 794 | ||
794 | err: | 795 | err: |
795 | kref_put(&uverbs_dev->ref, ib_uverbs_release_dev); | 796 | kref_put(&uverbs_dev->ref, ib_uverbs_release_dev); |
797 | wait_for_completion(&uverbs_dev->comp); | ||
798 | kfree(uverbs_dev); | ||
796 | return; | 799 | return; |
797 | } | 800 | } |
798 | 801 | ||
@@ -812,7 +815,10 @@ static void ib_uverbs_remove_one(struct ib_device *device) | |||
812 | spin_unlock(&map_lock); | 815 | spin_unlock(&map_lock); |
813 | 816 | ||
814 | clear_bit(uverbs_dev->devnum, dev_map); | 817 | clear_bit(uverbs_dev->devnum, dev_map); |
818 | |||
815 | kref_put(&uverbs_dev->ref, ib_uverbs_release_dev); | 819 | kref_put(&uverbs_dev->ref, ib_uverbs_release_dev); |
820 | wait_for_completion(&uverbs_dev->comp); | ||
821 | kfree(uverbs_dev); | ||
816 | } | 822 | } |
817 | 823 | ||
818 | static int uverbs_event_get_sb(struct file_system_type *fs_type, int flags, | 824 | static int uverbs_event_get_sb(struct file_system_type *fs_type, int flags, |