[PATCH] drm/amdgpu: Reserve shared fence slot in amdgpu_vm_update_directories

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

Without this, there could not be enough slots, which could trigger the
BUG_ON in reservation_object_add_shared_fence.

Cc: stable at vger.kernel.org
Bugzilla: https://bugs.freedesktop.org/106418
Reported-by: mikhail.v.gavrilov at gmail.com
Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 590db78b8c72..75579200f4a6 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1111,6 +1111,10 @@ int amdgpu_vm_update_directories(struct amdgpu_device *adev,
 		struct amdgpu_ring *ring;
 		struct dma_fence *fence;
 
+		r = reservation_object_reserve_shared(root->tbo.resv);
+		if (r)
+			return r;
+
 		ring = container_of(vm->entity.sched, struct amdgpu_ring,
 				    sched);
 
-- 
2.17.1