Re: kaybe lake panic

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

On Thu, Dec 19, 2019 at 05:37:44PM -0000, Christos Zoulas wrote:
> In article <20191219153115.GF1685@quartz>,
> Patrick Welche  <prlw1%cam.ac.uk@localhost> wrote:
> >Just tried NetBSD on a lapto that has what I think is a Kaybe lake
> >intel chip, and (no serial console - just copied off the screen):
> >
> >vpanic
> >snprintf
> >lockdebug_abort1
> >mutex_enter
> >execlists_update_context
> >execlists_context_unqueue
> >gen8_emit_request
> >__i915_add_request
> >i915_gem_init_hw
> >i915_gem_init
> >i915_driver_load
> >drm_dev_register
> >drm_pci_attach
> >i915drmkms_attach_real
> >config_mountroot_thread
> >
> >(x/s panicstr doesn't show me much)
> >
> >ps shows 2 x configroot, 2 x idle.
> >
> >What does one look for in show locks?
> >
> >Lock 0 initialized at drm_dev_alloc, sleep/adaptive, no active turnstile
> >
> >
> >Lock 0 initialized at main, spin, holds 0 excl 1, wants 0 excl 1
> >       curcpu holds 1 wanted by 000000000000000
> >Lock 1 initialized at logical_ring_init, spin, holds 0 excl 1, wants 0 excl 0
> >       wait/spin 0/1
> 
> does "show panic" work?

Yes:

Panic string: LOCKDEBUG: Mutex error: mutex_vector_enter,511: spin lock held

But according to lockdebug, the lock involving drm is not a spin lock, and
I can boot with "disable i915drmkms" ?!

I tried reboot 0x104, but:

# savecore -nv
dumplo = 109882880 (214615 * 512)
savecore: magic number mismatch (0x8b4cc845 != 0x8fca0101)
savecore: no core dump

Fair enough because I booted /netbsd not /netbsd.dbg (no LOCKDEBUG), but then:

# savecore -nvN /netbsd.dbg
savecore: kmem_setup:317: kvm_read dumpdev: kvm_read: Bad address
# savecore -vf .
dumplo = 109882880 (214615 * 512)
savecore: magic number mismatch (0x8b4cc845 != 0x8fca0101)
savecore: no core dump
savecore: warning: /dev/ksyms version mismatch:
        NetBSD 9.99.26 (QUARK) #405: Thu Dec 19 10:28:14 CET 2019
        prlw1@quark:/usr/src/sys/arch/amd64/compile/QUARK

and     ÿÿHxÿÿÿLUD]LMLþHÇÇ´è|\×

savecore: check_kmem:418: kvm_read msgbuf: _kvm_kvatop(e882d66500c7c748)
savecore: kvm_read msgbuf: _kvm_kvatop(6c749000003e6)
savecore: reboot after panic: 
savecore: system went down at (null)
savecore: dump time is unreasonable
savecore: ./bounds: No such file or directory
savecore: writing core to ./netbsd.0.core
savecore: writing kernel to ./netbsd.0
savecore: kvm_read ksyms: _kvm_kvatop(b7e900a6c88de882)
savecore: (null): Bad address


Cheers,

Patrick