[PATCH 1/1] drm/amdkfd: Protect the Client whilst it is being operated on

[Lee Jones]

Presently the Client can be freed whilst still in use.

Use the already provided lock to prevent this.

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-gfx@lists.freedesktop.org
Cc: dri-de...@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jo...@linaro.org>
---
 drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
index e4beebb1c80a2..3b9ac1e87231f 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
@@ -145,8 +145,11 @@ static int kfd_smi_ev_release(struct inode *inode, struct 
file *filep)
        spin_unlock(&dev->smi_lock);
 
        synchronize_rcu();
+
+       spin_lock(&client->lock);
        kfifo_free(&client->fifo);
        kfree(client);
+       spin_unlock(&client->lock);
 
        return 0;
 }
@@ -247,11 +250,13 @@ int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
                return ret;
        }
 
+       spin_lock(&client->lock);
        ret = anon_inode_getfd(kfd_smi_name, &kfd_smi_ev_fops, (void *)client,
                               O_RDWR);
        if (ret < 0) {
                kfifo_free(&client->fifo);
                kfree(client);
+               spin_unlock(&client->lock);
                return ret;
        }
        *fd = ret;
@@ -264,6 +269,7 @@ int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
        spin_lock(&dev->smi_lock);
        list_add_rcu(&client->list, &dev->smi_clients);
        spin_unlock(&dev->smi_lock);
+       spin_unlock(&client->lock);
 
        return 0;
 }
-- 
2.35.1.894.gb6a874cedc-goog