i386 ptrace - getting vm_areas structures / simd stuff

[Cedric ROUX]

Hi kernel hackers,

I'm coding a debugger (assembler-level, i386 processors to begin) and
I would like to get the virtual memories structures of the ptraced process
(its vm_areas).

Yes, I could read them in the binary file, then trace all syscalls to update
my informations (when a mmap occurs for example), but it seems to me it would
be better and easier to simply ask the kernel to return to me this information.

Or I even could use /dev/mem, a little tricky but not impossible... But I
prefer it to be in the kernel, what do you think ? (by the way, I could try
to add it in the kernel, if you too think it is useful). Or maybe there is
already a way to get this information ?

One other thing is the simd registers stuff. It'll be fun to be able to get/set
this (my 2.2.12 kernel does not have that in ptrace, a quick look in the 2.3.35
tells me there is nothing like that in there, a grep [sS][Ii][Mm][Dd] on all
the sources gives nothing too). Can I do it without run through a kernel call ?
Or is a ptrace extension needed ? Once again, I could help in this issue if you
think it's useful.

If you reply to me, please cc, I am not on the list.

Thank you,
Cedric.