Cockroach currently fails on SELinux (with default configurations) because it attempts to mmap a region of memory with PROT_WRITE and PROT_EXEC. Preliminary investigation shows that this is memory used for the stack.

According to this page (from 2011, don't know if it's still accurate), the executable bit for the stack is controlled by a link-time option. Somewhere in our build toolchain, that's not getting set correctly.