Re: [Valgrind-developers] valgrind [POSSIBLY UNSAFE] (fwd)

[Nicholas N. <nj...@ca...>]

On Sat, 24 Jan 2004, Jeremy Fitzhardinge wrote:

> All the dependencies on having to read /proc/self/maps before/after
> allocating various pieces of memory should be obsolete now.  This is
> because 1) the client hasn't run at all at this early stage, so there
> are no dynamically generated mappings, and 2) anyway, all client
> mappings are in the client address space, and all Valgrind mappings are
> above, so there's no likelihood of confusing the two.  I don't know if
> this actually makes any difference, but it seemed like a couple of
> things were initialized in somewhat unnatural places because of this old
> constraint.

You're welcome to change it;  I'm reluctant to do so because I'm not
familiar enough with how memory is laid out at the start.

> Also, I think read and parse of /proc/self/maps were separated because
> it was quite common to read /proc/self/maps once, then parse it multiple
> times for various reasons (in fact, main() does this now).  I think this
> is still a useful thing to have, though reading /proc/self/maps should
> now only be necessary during startup, since after that the Segment list
> will tell you everything you need to know about the layout of the
> address space.

/proc/self/maps is read once, and parsed twice, all within main() before
running the client.  Also, the two parsings happen one after another, in a
way that made me think they could be combined.

N