Hello,

So I am trying to make a simple 5 pt stencil finite difference laplacian 
operator (https://akmitra.public.iastate.edu/aero361/design_web/Laplace.pdf) 
work on a dmplex mesh, but all of the examples that I have found in 
ksp/examples/tutorials all use DMDA. The only way that I have managed to get 
the KSP to even run is by creating the operator matrix myself by hand. The 
workflow for the working implementation is as follows:

DMPlexMakeBoxMesh -> KSPCreate -> KSPsetDM -> KSPDeactiveDM -> Make the matrix 
by hand ->  KSPSetOperator(matrix) -> KSPSetComputeRHS -> Solve

Given that I tether KSP to the DM by KSPSetDM, but then immediately deactivate 
it (because then it complains about mallocs), this doesn’t work when reading in 
an actual unstructured mesh. Does KSP just not support dmplex?

Best,

Jacob

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