drm/radeon: move IB pool to 1MB offset

Even GPUs can have a null pointer dereference, so move
the IB pool to another offset to catch those.

Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon_ring.c b/drivers/gpu/drm/radeon/radeon_ring.c
index 993cf71..d90b0bc 100644
--- a/drivers/gpu/drm/radeon/radeon_ring.c
+++ b/drivers/gpu/drm/radeon/radeon_ring.c
@@ -79,10 +79,10 @@
 	ib->ptr = radeon_sa_bo_cpu_addr(ib->sa_bo);
 	ib->vm = vm;
 	if (vm) {
-		/* ib pool is bind at 0 in virtual address space,
-		 * so gpu_addr is the offset inside the pool bo
+		/* ib pool is bound at RADEON_VA_IB_OFFSET in virtual address
+		 * space and soffset is the offset inside the pool bo
 		 */
-		ib->gpu_addr = ib->sa_bo->soffset;
+		ib->gpu_addr = ib->sa_bo->soffset + RADEON_VA_IB_OFFSET;
 	} else {
 		ib->gpu_addr = radeon_sa_bo_gpu_addr(ib->sa_bo);
 	}