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8b6b7d84bf
I honestly don't exactly understand what's going on here, but the current code is wrong for sure: It calls dma_buf_vunmap without ever calling dma_buf_vmap. What I'm not sure about is whether the WARN_ON is correct: - msm imports dma-buf using drm_prime_sg_to_page_addr_arrays. Which is a pretty neat layering violation of how you shouldn't peek behind the curtain of the dma-buf exporter, but par for course. Note that all the nice new helpers don't (and we should probably have a bit a warning about this in the kerneldoc). - but then in the get_vaddr() in msm_gem.c, we seems to happily wrap a vmap() around any object with ->pages set (so including imported dma-buf). - I'm not seeing any guarantees that userspace can't use an imported dma-buf for e.g. MSM_SUBMIT_CMD_BUF in a5xx_submit_in_rb, so no guarantees that an imported dma-buf won't end up with a ->vaddr set. But even if that WARN_ON is wrong, cleaning up a vmap() done by msm by calling dma_buf_vunmap is the wrong thing to do. v2: Rob said in review that we do indeed have a gap in get_vaddr() that needs to be plugged. But the users I've found aren't legit users on imported dma-buf, so we can just reject that. Reviewed-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Rob Clark <robdclark@gmail.com> Cc: Sean Paul <sean@poorly.run> Cc: linux-arm-msm@vger.kernel.org Cc: freedreno@lists.freedesktop.org Link: https://patchwork.freedesktop.org/patch/msgid/20200514201117.465146-1-daniel.vetter@ffwll.ch |
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| .. | ||
| adreno | ||
| disp | ||
| dsi | ||
| edp | ||
| hdmi | ||
| Kconfig | ||
| Makefile | ||
| msm_atomic.c | ||
| msm_atomic_trace.h | ||
| msm_atomic_tracepoints.c | ||
| msm_debugfs.c | ||
| msm_debugfs.h | ||
| msm_drv.c | ||
| msm_drv.h | ||
| msm_fb.c | ||
| msm_fbdev.c | ||
| msm_fence.c | ||
| msm_fence.h | ||
| msm_gem.c | ||
| msm_gem.h | ||
| msm_gem_prime.c | ||
| msm_gem_shrinker.c | ||
| msm_gem_submit.c | ||
| msm_gem_vma.c | ||
| msm_gpu.c | ||
| msm_gpu.h | ||
| msm_gpu_trace.h | ||
| msm_gpu_tracepoints.c | ||
| msm_gpummu.c | ||
| msm_iommu.c | ||
| msm_kms.h | ||
| msm_mmu.h | ||
| msm_perf.c | ||
| msm_rd.c | ||
| msm_ringbuffer.c | ||
| msm_ringbuffer.h | ||
| msm_submitqueue.c | ||
| NOTES | ||