diff options
| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2020-07-27 23:30:18 +0200 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2020-07-30 15:36:44 -0400 |
| commit | 178b0013f074da545492662ec76dc2be363ca85c (patch) | |
| tree | 134f00356eb1f4606447766ec91b24a3a28e38a4 | |
| parent | 317469f695c27e290b8001a0df0fdbb95f27bfa9 (diff) | |
drm/amdgpu/dc: Stop dma_resv_lock inversion in commit_tail
Trying to grab dma_resv_lock while in commit_tail before we've done
all the code that leads to the eventual signalling of the vblank event
(which can be a dma_fence) is deadlock-y. Don't do that.
Here the solution is easy because just grabbing locks to read
something races anyway. We don't need to bother, READ_ONCE is
equivalent. And avoids the locking issue.
v2: Also take into account tmz_surface boolean, plus just delete the
old code.
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: linux-rdma@vger.kernel.org
Cc: amd-gfx@lists.freedesktop.org
Cc: intel-gfx@lists.freedesktop.org
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
| -rw-r--r-- | drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 19 |
1 files changed, 6 insertions, 13 deletions
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 4b32862879130..342663fcd44d7 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -7081,20 +7081,13 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state, DRM_ERROR("Waiting for fences timed out!"); /* - * TODO This might fail and hence better not used, wait - * explicitly on fences instead - * and in general should be called for - * blocking commit to as per framework helpers + * We cannot reserve buffers here, which means the normal flag + * access functions don't work. Paper over this with READ_ONCE, + * but maybe the flags are invariant enough that not even that + * would be needed. */ - r = amdgpu_bo_reserve(abo, true); - if (unlikely(r != 0)) - DRM_ERROR("failed to reserve buffer before flip\n"); - - amdgpu_bo_get_tiling_flags(abo, &tiling_flags); - - tmz_surface = amdgpu_bo_encrypted(abo); - - amdgpu_bo_unreserve(abo); + tiling_flags = READ_ONCE(abo->tiling_flags); + tmz_surface = READ_ONCE(abo->flags) & AMDGPU_GEM_CREATE_ENCRYPTED; fill_dc_plane_info_and_addr( dm->adev, new_plane_state, tiling_flags, |