[meta-freescale] imx6 silent memory corruption

[Otavio Salvador]

On Tue, Jan 27, 2015 at 2:27 PM, Nikolay Dimitrov <picmaster at mail.bg> wrote:
> Just to share my progress so far. My board passed 500+ iterations of
> DDR stress testing with the FSL tool (this bloody thing took 2 days to
> complete!). Tried the U-Boot integrated memory tests (both quick and
> alt), and they didn't show any issues. So I can say that at least the
> hardware and DDR settings seems to be OK.
>
> In addition, I tried to disable SMP, L2 & L1 cache support in my kernel
> and see what happens, but I can still observe the corruption. I found
> that there's an embedded memory tester in the kernel, but only for x86
> (CONFIG_MEMTEST), not useful for ARM.
>
> I started to doubt that my 2 cross-build machines (x64 Debian stable)
> are maybe producing broken kernels, so did a test cross-build on Ubuntu
> 14.04, and even did native build on riotboard, but the results are the
> same - issue can be still observed.
>
> During boot and operation I sometimes see kernel oopses (I remember
> most of them related with execve and filesystem reads), sometimes apps
> segfault. Kernel and/or toolchain issues are also possible but I
> checked that Daisy has the gcc-4.8+ PR58854 patch, so not very likely,
> especially if other Yocto users don't report such issues.
>
> Possible step forward is to try to build original FSL 3.10.17 version
> without my local patches, and maybe even build a minimal 3.18+ mainline
> kernel to see how it behaves in the same test case. Someone can even
> joke that it's time to leave the dusty old Daisy and go forward with
> Dizzy and 3.10.53.

I think Dizzy is very solid. We have been using this with several
customers and been very satisfied.


-- 
Otavio Salvador                             O.S. Systems
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