Re: Red Pitaya 122-16: kernel reaches init!

[David Young <dyoung%pobox.com@localhost>]

On Sun, Mar 31, 2024 at 12:18:33PM -0500, David Young wrote:
> Today I got the NetBSD kernel to start on this Red Pitaya 122-16 using a
> device tree derived from zynq-zybo-z7.dts.  An important difference that
> I only noticed yesterday is that the Zybo Z7 and the 122-16 have their
> consoles on different UARTs.
*snip snip*
> The system gets as far as starting init before it crashes.  Here is a
> typescript.
> 
*snip snip*
> [  31.4100050] uvm_fault(0x80c8bb08, 61632000, 1) -> e
> [  31.4100050] Fatal kernel mode data abort: 'Translation Fault (S)'
> [  31.4100050] trapframe: 0xa6cc5c58
> [  31.4200050] FSR=00000005, FAR=6163203e, spsr=20000013
> [  31.4200050] r0 =80736aec, r1 =90186000, r2 =6163203a, r3 =807b83f8
> [  31.4300050] r4 =90ce9b80, r5 =90ce9b80, r6 =00000000, r7 =90186004
> [  31.4400050] r8 =00000000, r9 =90186000, r10=80736ae0, r11=a6cc5cf4
> [  31.4400050] r12=a6cc5c38, ssp=a6cc5ca8, slr=804d2eb8, pc =8049650c
> 
> Stopped in pid 164.164 (init) at        netbsd:uvm_pgflcache_spill+0xa4:        
> ldr     r12, [r2, #0x004]
> db{1}> bt
> 0xa6cc5cf4: netbsd:uvm_pgflcache_spill+0x10
> 0xa6cc5d24: netbsd:uvm_pgflcache_free+0x160

An init(8) error message has overwritten part of the free-page list.
That is where the address in r2, 0x6163203a or ": ca", comes from:

db{1}> x/c 0x90186000,4096                        
90186000:       init: can't get /dev/console for controlling terminal: Operation
90186040:        not supported\015\012\000\000\000\000\377\230\377\377\000\000\0
00\000\377\377\377\377\000\000\000\000\377\377\377\377\000\000\000\000\377\377\3
77\377\000\000\000\000\377\377\377\377\000\000\000\000\377\377\377\377\000\000\0
. . .

I don't know how this has happened.  Maybe there is a bug in the early
console driver?

David

-- 
David Young
dyoung%pobox.com@localhost    Urbana, IL    (217) 721-9981