Re: Hopefully a simple question on /proc/pid/mem

Stephen C. Tweedie
2001-04-30T21:58:02Z

Hi,

On Mon, Apr 30, 2001 at 03:02:40PM -0400, Benjamin C.R. LaHaise wrote:
> On Mon, 30 Apr 2001, Alexander Viro wrote:
>
> > I wonder what's wrong with reading from /proc/<pid>/mem, though - it's
> > using the same code as ptrace.
>
> We can actually do this cleanly now that we have proper page_dirty
> semantics for raw io. The original reason for disabling /proc/*/mem was
> that it left big gaping holes in the mm code in 2.0, and it hasn't been
> repaired since.

It was mmap of /proc/*/mem which was busted. read/write should be OK.

Hint: think about what happens if you make a shared mapping of a
private proc/*/mem region...

--Stephen