Hello, I _might_ be doing something wrong when calling KSPSetFromOptions/KSPSetUp, but still, am I supposed to get this kind of error? [0]PETSC ERROR: No support for this operation for this object type [0]PETSC ERROR: KSP gmres does not support PRECONDITIONED with RIGHT If not, I’ll try to send a MWE (it basically depends on where I set the option -ksp_pc_side right). Thanks, Pierre