I've looked at reassigning the following Mesa bug report to libdrm.

https://bugs.freedesktop.org/show_bug.cgi?id=91082

but I can't seem to do so, or what is more correct I don't know how too.

The following patch:

Fabrice Bellet, change to libDRM:
intel/intel_bufmgr_gem.c
https://bugs.freedesktop.org/attachment.cgi?id=122880

Fixes a crash I was seeing in Mesa when I have two threads, each with an X11
display connection and each with an OpenGL context.

Each context is tied to the X11 Display, they are not swapped or used from
another Display connection.

The only resource shared between the two contexts are texture IDs.