[PATCH 1/4] drm/radeon: fix lockup when BOs aren't part of the VM on release

[Christian König]

On 27.04.2015 17:04, Christian König wrote:
> From: Christian König <christian.koenig at amd.com>
>
> If we unmap BOs before releasing them them the intervall tree locks
> up because we try to remove an entry not inside the tree.
>
> Signed-off-by: Christian König <christian.koenig at amd.com>
> CC: stable at vger.kernel.org

Somehow forgot to mention that Michel is the original author of this 
patch, I just fixed two additional lines which caused list corruption.

Regards,
Christian.

> ---
>   drivers/gpu/drm/radeon/radeon_vm.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/radeon/radeon_vm.c b/drivers/gpu/drm/radeon/radeon_vm.c
> index 2a5a4a9..16d8e95 100644
> --- a/drivers/gpu/drm/radeon/radeon_vm.c
> +++ b/drivers/gpu/drm/radeon/radeon_vm.c
> @@ -1107,7 +1107,8 @@ void radeon_vm_bo_rmv(struct radeon_device *rdev,
>   	list_del(&bo_va->bo_list);
>   
>   	mutex_lock(&vm->mutex);
> -	interval_tree_remove(&bo_va->it, &vm->va);
> +	if (bo_va->it.start || bo_va->it.last)
> +		interval_tree_remove(&bo_va->it, &vm->va);
>   	spin_lock(&vm->status_lock);
>   	list_del(&bo_va->vm_status);
>