[Openmcl-devel] CCL trunk on Linux ARM / Ubuntu - Unhandled exception 4

[Rainer Joswig]

Am 31.05.2014 um 11:35 schrieb Gary Byers <gb at clozure.com>:

> I don't have a good guess, but another bad guess is that this is an instruction
> cache problem.  (For anyone who cares: most RISC machines have separate instruction
> and data caches; the X86 has a unified cache.  When machine code is written to
> memory, it's often actually only written to the data cache and isn't actually
> loaded into the instuction cache unless special steps are taken.  A typical
> symptom of failing to take those steps is that the processor executes code
> "that isn't there" (what the processor actually executes isn't consistent
> with what appears to be in memory.)

Gary, here is another data point.

The ODROID XU has a big.LITTLE CPU.

Exynos5 Octa Cortex™-A15 1.6Ghz quad core and Cortex™-A7 quad core CPUs

Exynos 5410 


It seems that it runs fine on the big cores and crashes on the LITTLE cores.

If I start CCL when the CPU is using the big cores, CCL runs fine.
If I start CCL when the CPU is using the little cores, CCL crashes.


If I start CCL when the CPU is using the big cores, CCL runs fine. Switching back to the little ones, then crashes the crunning CCL.