7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jesse Zhang commit 3c44cbcec5eb370713bbd2c315ed7c34d8ccec2b upstream. amdgpu_gem_object_close() detaches the user queue eviction fence from the BO before it checks bo_va->ref_count, so closing any handle of a BO removes the fence, even when the file still has another handle to the BO and the bo_va with its GPU mappings stays. The BO can then be evicted without suspending the user queues of the file, which keep accessing it through mappings that are only marked for update. Seen on navi31 with a SDMA user queue: a BO opened twice in the same file (GEM_FLINK + GEM_OPEN) loses its eviction fence when the second handle is closed (traced attach/detach of the fence): attach bo=ffff8c78a6c84c00 GEM_CLOSE handle=7 detach bo=ffff8c78a6c84c00 while handle 6 and the mapping are still in use. Only detach the fence when the last reference to the bo_va goes away, matching amdgpu_gem_object_open(), which attaches it only when the bo_va is created. With this the fence stays until the file is closed. Fixes: 31f7efcdca4d ("drm/amdgpu: enable eviction fence") Signed-off-by: Jesse Zhang Reviewed-by: Christian König Signed-off-by: Alex Deucher (cherry picked from commit 8387982f03d4026b7dc11b0b5e3118298eee4d6a) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c @@ -337,11 +337,14 @@ static void amdgpu_gem_object_close(stru goto out_unlock; } + bo_va = amdgpu_vm_bo_find(vm, bo); + /* the fence is attached once per bo_va, so keep it for other handles */ + if (bo_va && --bo_va->ref_count) + goto out_unlock; + if (!amdgpu_vm_is_bo_always_valid(vm, bo)) amdgpu_evf_mgr_detach_fence(&fpriv->evf_mgr, bo); - - bo_va = amdgpu_vm_bo_find(vm, bo); - if (!bo_va || --bo_va->ref_count) + if (!bo_va) goto out_unlock; amdgpu_vm_bo_del(adev, bo_va);