There was a small window between unreserve and second reserve where the
freshly allocated BO could have been evicted without the VM noticing it.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>