This ensures userspace cannot prematurely clean-up the client before
it is fully initialised which has been proven to cause issues in the
past.
Cc: Felix Kuehling <felix.kuehl...@amd.com>
Cc: Alex Deucher <alexander.deuc...@amd.com>
Cc: "Christian König" <christian.koe...@amd.com>
Cc: "Pan, Xinhui" <xinhui....@amd.com>
Cc: David Airlie <airl...@linux.ie>
Cc: Daniel Vetter <dan...@ffwll.ch>
Cc: amd-...@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jo...@linaro.org>
---
CAVEAT: This patch is completely untested
I can't seem to find a configuration strategy to compile test this
allyesconfig and allmodconfig do not appear sufficient
v2: Also remove Client from RCU list in error path
drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c | 24 +++++++++++++--------
1 file changed, 15 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
index e4beebb1c80a2..f2e1d506ba211 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
@@ -247,15 +247,6 @@ int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
return ret;
}
- ret = anon_inode_getfd(kfd_smi_name, &kfd_smi_ev_fops, (void *)client,
- O_RDWR);
- if (ret < 0) {
- kfifo_free(&client->fifo);
- kfree(client);
- return ret;
- }
- *fd = ret;
-
init_waitqueue_head(&client->wait_queue);
spin_lock_init(&client->lock);
client->events = 0;
@@ -265,5 +256,20 @@ int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
list_add_rcu(&client->list, &dev->smi_clients);
spin_unlock(&dev->smi_lock);
+ ret = anon_inode_getfd(kfd_smi_name, &kfd_smi_ev_fops, (void *)client,
+ O_RDWR);
+ if (ret < 0) {
+ spin_lock(&dev->smi_lock);
+ list_del_rcu(&client->list);
+ spin_unlock(&dev->smi_lock);
+
+ synchronize_rcu();
+
+ kfifo_free(&client->fifo);
+ kfree(client);
+ return ret;
+ }
+ *fd = ret;
+
return 0;
}
--
2.35.1.1021.g381101b075-goog
