From 9fc15f5fc836712b173f04e143b8d77fdded1a37 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Nicolai=20H=C3=A4hnle?= Date: Fri, 29 Jun 2018 13:23:25 +0200 Subject: [PATCH] drm/amdgpu: fix user fence write race condition MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The buffer object backing the user fence is reserved using the non-user fence, i.e., as soon as the non-user fence is signaled, the user fence buffer object can be moved or even destroyed. Therefore, emit the user fence first. Both fences have the same cache invalidation behavior, so this should have no user-visible effect. Signed-off-by: Nicolai Hähnle Reviewed-by: Alex Deucher Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c index 31f8170313b4..ce7739832d29 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c @@ -231,6 +231,12 @@ int amdgpu_ib_schedule(struct amdgpu_ring *ring, unsigned num_ibs, if (ib->flags & AMDGPU_IB_FLAG_TC_WB_NOT_INVALIDATE) fence_flags |= AMDGPU_FENCE_FLAG_TC_WB_ONLY; + /* wrap the last IB with fence */ + if (job && job->uf_addr) { + amdgpu_ring_emit_fence(ring, job->uf_addr, job->uf_sequence, + fence_flags | AMDGPU_FENCE_FLAG_64BIT); + } + r = amdgpu_fence_emit(ring, f, fence_flags); if (r) { dev_err(adev->dev, "failed to emit fence (%d)\n", r); @@ -243,12 +249,6 @@ int amdgpu_ib_schedule(struct amdgpu_ring *ring, unsigned num_ibs, if (ring->funcs->insert_end) ring->funcs->insert_end(ring); - /* wrap the last IB with fence */ - if (job && job->uf_addr) { - amdgpu_ring_emit_fence(ring, job->uf_addr, job->uf_sequence, - fence_flags | AMDGPU_FENCE_FLAG_64BIT); - } - if (patch_offset != ~0 && ring->funcs->patch_cond_exec) amdgpu_ring_patch_cond_exec(ring, patch_offset); -- 2.30.2