Re: mips64 and GCC 5

[Nick Hudson <skrll%netbsd.org@localhost>]

On 10/06/16 16:49, John D. Baker wrote:
> Some things I observed in my earlier trial of GCC 5 on my Lemote YeeLoong
> (LOONGSON-derived kernel), now borne out with the official switch of
> mips64 ports to GCC 5:
[snip]

> pid 1005(find): trap: cpu0, address error (load or I-fetch) in kernel mode
> status=0x8400ffa3, cause=0x10, epc=0xffffffff804007a4, vaddr=0x98000000854a001a
> tf=0x98000000812cba40 ksp=98000000812cbb80 ra=0xffffffff804007a4 pp1=0x4000
> kernel: address error (load or I-fetch) trap
> Stoped in pid 1005.1 (find) at ffffffff804007a4:      lwu     v0,0(s0)
> db> bt
> 0x98000000812cbb80: 0+ffffffff804007a4 (98000000bf459418,0,98000000bf459208,98000000bf459248) ra 0 sz 0
> User-level: pid 1005.1
>
> I've seen this happen before, but hadn't recently until now.
>
> A curious thing is that DDB output isn't rendered on the screen unless
> one switches to another virtual terminal and back again.

I think I fixed this at least partly.

Can you test with latest HEAD? You might get more luck with removing 
ENABLE_MIPS_16KB_PAGE from

https://nxr.netbsd.org/xref/src/sys/arch/evbmips/conf/std.loongson#7

Nick