On Sun, 30 Jun 2019 at 10:28, Jason Thorpe <thor...@me.com> wrote: > > > > On Jun 30, 2019, at 6:46 AM, Andrew Cagney <andrew.cag...@gmail.com> wrote: > > > > Things started to go down hill when the debugger developers decided > > that rooting around in the process to extract the memory map was "a > > good idea". After all, it too is likely been corrupted by the crashing > > program. > > > > There's /proc/PID/maps, there should be a PTRACE equivalent and it > > should also be dumped into the core file. > > Certainly, the ELF core files dumped by NetBSD have a PT_LOAD section for > each VM map entry, so the memory map information is already there.
Right (with debugger magic filling in the missing but listed read-only segments). > Now, for mapped files, it doesn't record the path name like you get with > /proc/PID/maps, but that's something that could be fixed by having one or > more additional PT_NOTE sections where the note contains a PT_LOAD index to > file name mapping (with the path string being contained in the note). What ever the format it might as well be consistent between /proc, ptrace() and core dumps, and should accommodate variable length paths (unlike the current core file structure). Spewing /proc/pid/maps (actually, much of /proc/pid) as one or more notes into core file is a good starting point (and one known to work). Other formats are also valid. (I thought 9 had forked) > -- thorpej >
