  General local half-BPS solutions in M-theory, which have $SO(2,2)\times
SO(4)\times SO(4)$ symmetry and are asymptotic to $AdS_{7}\times S^{4}$, were
constructed in exact form by the authors in [arXiv:0806.0605]. In the present
paper, suitable regularity conditions are imposed on these local solutions, and
corresponding globally well-defined solutions are explicitly constructed. The
physical properties of these solutions are analyzed, and interpreted in terms
of the gravity duals to extended 1+1-dimensional half-BPS defects in the
6-dimensional CFT with maximal supersymmetry.
