Matrix operations 2

[Andrey]

Dear CP2K developers,

I have the following part of code
..........
              DO ispin=1,nspins
                  CALL integrate_four_center(qs_env,
exx_kernel,exx_energy,&
                                     rho1,tddft_hfx_section,qs_env
%para_env,&
                                     qs_env%ks_env%s_mstruct_changed,
1,.TRUE.,&
                                     ispin=ispin, error=error)
              END DO
...........

It crashes (forrtl: severe (174): SIGSEGV, segmentation fault
occurred) while passing hfx_energy_potential.F:

1896       !! ** Calculate the exchange energy
1897         CALL cp_dbcsr_trace(ks_matrix(ispin)%matrix, rho_ao(ispin)
%matrix, &
1898                             ene_x_aa, error=error)

Here, the ks_matrix is the distributed full_ks matrix, containing all
exchange integrals.
rho_ao => rho%rho_ao (filtered atomic basis sets)

1) How can I output the ks_matrix and rho_ao matrices to analyse them?
2) What type of error may lead to such sort of crash?

Best Regards,
Andrey