[Beignet] How widespread is "Exec event...error...-5" (#98647 / #100639)?

[Rebecca N. Palmer]

Debian 9 (stretch)/Ubuntu 17.04 (zesty) have beignet 1.3.0, libdrm 
2.4.74/2.4.76 and Linux 4.9/4.10.

On some hardware (possibly all of Ivy Bridge and Haswell??), this does 
not work at all: attempting to run anything fails with

drm_intel_gem_bo_context_exec() failed: Device or resource busy
Beignet: "Exec event 0xnnnn error, type is 4592, error staus is -5"

https://bugs.freedesktop.org/show_bug.cgi?id=98647
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=860805

As the package maintainer, I'd like to fix this.  I am aware of two 
fixes, either of which works for me, but 
https://bugs.freedesktop.org/show_bug.cgi?id=100639 reports that neither 
of them is perfect:

  - The fix used in 1.4: 
https://cgit.freedesktop.org/beignet/commit/?id=8b04f0be372da8eabdc93d6ae1b81a3c83cba284

- Disable HAS_BO_SET_SOFTPIN: fixes more (but still not everything), but 
also disables some functionality (OpenCL 2.0).  This is probably why the 
bug only appears in recent Linux versions, and hence was missed when I 
tested the packages in a chroot on Linux 3.16: softpin was only 
introduced in Linux 4.5.

Has anyone other than its reporter seen #100639 (i.e. this error 
persisting after applying the 1.4 fix, particularly when using multiple 
OpenCL kernels such as in clFFT)?

Any other suggestions?