Re: A possible libc/dlmopen/pthreads bug

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

On 24/01/2018 15:46, Vivek Das Mohapatra wrote:
>> In fact I think Vivek examples of running process with two different libcs
>> are working mainly because the different glibc define and access the shared
>> resources in same manner.  I bet it will break the moment we change some
>> state internal layout or semantic (for instance the __stack_user struct size).
> 
> A slight correction - we are deliberately using the _same_ libc to
> avoid exactly that problem - it's that dlmopen as currently implemented
> creates a new mapping of the same libc for the dlmopen namespace.
> 
> I also don't need (or expect) complete isolation of the libc cluster:
> If I could, I would share the same mapping of libc & co with the main
> link map.

Right, you first message gave the impression based on the provided
chart that you expected libc isolation as well. I still think we should
clarify the dlmopen semantics, but we can work on this through bug
reports and issue like this one you brought.

I think best course of action is still open a bug report with a possible
testcase.  I will ping Carlos to check his idea about it, he seemed
interested with previous dlmopen issues.