Instability likely related to new pmap on Cubieboard A10

[Ian Lepore]

On Wed, 2015-08-19 at 03:21 +0300, Dmitry Marakasov wrote:
> Hi!
> 
> I've just tried latest HEAD on cubieboard A10, and discovered that
> it's completely unstable. Kernel boots without problems, however
> right after init is started many processes crash with sigsegv and
> other errors, and it ends with either hang or a panic. Examples
> below. With kernel built with `nooptions ARM_NEW_PMAP' these
> problems go away. Feel free to ask for any additional info.
> 
> ---
> [...]
> ---
> 

That is, frankly, just hard to accept as real.  ARM_NEW_PMAP has been
the default for like 8 months.  If it was that broken, the first report
of it would have come in much earlier than this.  That seems more like
some sort of broken or corrupted binary, and perhaps the problem went
away not because the option changed, but because changing the option
rebuilt whatever was corrupted.

Actually, given that everything was fine until userland started, and
"bad syscall" shows up a lot in the errors, a kernel/userland mismatch
also seems like a good candidate.

-- Ian