The prev context is the MMU context at the time of the job queueing in hardware. As a job might be queued multiple times due to recovery after a GPU hang, we need to make sure to put the stale prev MMU context from a prior queuing, to avoid the reference and thus the MMU context leaking.
Cc: stable@vger.kernel.org # 5.4 Signed-off-by: Lucas Stach l.stach@pengutronix.de Tested-by: Michael Walle michael@walle.cc --- drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c index c8b9b0cc4442..c1b9c5cbed11 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c @@ -1368,6 +1368,8 @@ struct dma_fence *etnaviv_gpu_submit(struct etnaviv_gem_submit *submit) gpu->mmu_context = etnaviv_iommu_context_get(submit->mmu_context); etnaviv_gpu_start_fe_idleloop(gpu); } else { + if (submit->prev_mmu_context) + etnaviv_iommu_context_put(submit->prev_mmu_context); submit->prev_mmu_context = etnaviv_iommu_context_get(gpu->mmu_context); }