Hi Rumen,
here is an example output of "info proc mappings" on base-linux:
... 0x7ffbe6e00000 0x7ffbe6e01000 0x1000 0x0 rw-s /tmp/genode-1000/ds-752 (deleted) 0x7ffbe6e01000 0x7ffbe6e10000 0xf000 0x0 ---p 0x7ffbe6e10000 0x7ffbe6e20000 0x10000 0x0 rw-s /tmp/genode-1000/ds-915 (deleted) 0x7ffbe6e20000 0x7ffbe6e40000 0x20000 0x0 ---p 0x7ffbe6e40000 0x7ffbe6e80000 0x40000 0x0 rwxs /tmp/genode-1000/ds-938 (deleted) 0x7ffbe6e80000 0x7ffbe6f00000 0x80000 0x0 rwxs /tmp/genode-1000/ds-835 (deleted) ...
The managed dataspace region goes from 0x7ffbe6e00000 to 0x7fffe6dfffff. When a dataspace is attached to the region the corresponding permissions are shown and holes between the dataspaces are shown as ---p.
Could you check if the ' _obj_space.attach()' call actually succeeded? Or if the result is different when you attach '_obj_space' to 'env.rm()' first and then the dataspace to '_obj_space'?
Christian