Oscillatory null singularity inside realistic spinning black holes

We calculate the asymptotic behavior of the curvature scalar $(Riemann)^2$ near the null weak singularity at the inner horizon of a generic spinning black hole, and show that this scalar oscillates infinite number of times while diverging. The dominant parallelly-propagated Riemann components oscillate in a similar manner. This oscillatory behavior, which is in a remarkable contrast to the monotonic mass-inflation singularity in spherical charged black holes, is caused by the dragging of inertial frames due to the black- hole's spin.