Hello, I run a program on machines, say, A and B. The program is (a simple code that does nothing) compiled on A and stopped (put to sleep, with getch() or something) at the same point. When I examine their address spaces by looking /proc/<pid>/maps, I see that some of the vmas are mapped to different locations on A and B. I looked at the code for load_elf_binary in fs/binfmt_elf.c, it is quite complicated. Who decides where these segments get mapped? Is it (1) load_elf_binary() or (2) mmap() or are they set at (3) compile/link time? The (3) seems not, as the program is compiled on A and ran on both. I learned from Martin Loewis that: - exact setting of the enviroment variables (in the strict sense of execve) - size, contents, and layout of /etc/ld.so.cache - path name of each file that is being loaded - contents of each directory that is searched when loading shared libraries, and exact order of entries returned by getdents(2) - value of cwd string are some of the factors that affect the location of maps. Is there a way to make or guarantee these segments - a process'/library's data segment, etc. - get mapped at the same location across machines? Maybe by a customized elf binary handler? -- Muzaffer Ozakca Researcher/Software Engineer - muzaffer.ozakca@bilten.metu.edu.tr TUBITAK-Bilten-ODTU - Communication Systems and Comp. Networks Group ODTU, Ankara, Turkey http://www.bilten.metu.edu.tr/ tel: +90-312-210 1311 -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ IRC Channel: irc.openprojects.net / #kernelnewbies Web Page: http://www.kernelnewbies.org/
