Mesh deformation with GMG not working

[alarshi]

When we use spherical geometry with imposed topography using the mesh deformation plugin and GMG solver, we get the following error in deal.II. On the other hand, box geometry with GMG and mesh deformation works okay.

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An error occurred in line <760> of file </home/arushi/opt/tmp/unpack/deal.II-v9.5.1/include/deal.II/lac/affine_constraints.templates.h> in function
    void dealii::AffineConstraints<number>::close() [with number = double]
The violated condition was: 
    dof_index != constrained_line.entries[i].first
Additional information: 
    Cycle in constraints detected!

Stacktrace:
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#0  /home/arushi/opt/deal.II-v9.5.1/lib/libdeal_II.g.so.9.5.1: dealii::AffineConstraints<double>::close()
#1  /home/arushi/opt/deal.II-v9.5.1/lib/libdeal_II.g.so.9.5.1: dealii::AffineConstraints<double>::merge(dealii::AffineConstraints<double> const&, dealii::AffineConstraints<double>::MergeConflictBehavior, bool)
#2  /home/arushi/opt/aspect-main/build/aspect: dealii::MGConstrainedDoFs::add_user_constraints(unsigned int, dealii::AffineConstraints<double> const&)
#3  /home/arushi/opt/aspect-main/build/aspect: aspect::MeshDeformation::MeshDeformationHandler<2>::compute_mesh_displacements_gmg()
#4  /home/arushi/opt/aspect-main/build/aspect: aspect::MeshDeformation::MeshDeformationHandler<2>::execute()
#5  /home/arushi/opt/aspect-main/build/aspect: aspect::Simulator<2>::solve_timestep()
#6  /home/arushi/opt/aspect-main/build/aspect: aspect::Simulator<2>::run()
#7  /home/arushi/opt/aspect-main/build/aspect: void run_simulator<2>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, bool, bool, bool)
#8  /home/arushi/opt/aspect-main/build/aspect: main
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I am testing with this parameter file : spherical_mesh_deformation_gmg.txt
input_1deg_topography.txt

[tjhei]

Can you check if
https://github.com/geodynamics/aspect/blob/12bb3bf746c448a23941bf5def5e46970cf06a45/source/mesh_deformation/interface.cc#L1070C36-L1070C36 sould use tangential_mesh_deformation_boundary_indicators instead of asking the boundary_velocity_manager? (maybe print the two sets and check if they are different in this case)

[alarshi]

In this test, tangential_mesh_deformation_boundary_indicators only outputs the inner boundary while boundary_velocity_manager includes both the inner and the outer boundaries.
I get the same error message as before with the tangential_mesh_deformation_boundary_indicators.