Hello, As of v6.5 cat /proc/*/maps produces empty output on nommu xtensa systems. Bisection points to the commit 0c563f148043 ("proc: remove VMA rbtree use from nommu"). It looks like the issue may be not in the m_start (where find_vma(mm, addr) returns NULL), but in the nommu version of find_vma itself. I've tried replacing nommu find_vma implementation with an implementation of the MMU version and it fixes the /proc/*/maps output. Kind of (it works as expected on one of my systems, but consistently locks up on the other). Any suggestions of what might be wrong/how to fix it properly? -- Thanks. -- Max