Re: panic in drm or vt or deadlock on mutex or ...

On 2021-02-08 21:01, Hans Petter Selasky wrote:
> On 2/8/21 1:53 PM, Alastair Hogge wrote:
>> Boot to multi-user; login (getty):
>> $ doas kldload /boot/modules/amdgpu.ko
>> $ sysctl
>> [panic]
>>
>> ..is a guaranteed way to panic my system.
> 
> Hi,
> 
> Maybe you could do a hack and edit the sysctl source code:
> 
> 1) print the sysctl before it is queried.
> 2) sleep 1 second between print and query.
> 
> Should be easy to nail this down!

Always panics at:
$ /tmp/sysctl-with-delay -a
[...]
p1003_1b.mapped_files: 200112
p1003_1b.memlock: 0
p1003_1b.memlock_range: 0
p1003_1b.memory_protection: 0
p1003_1b.message_passing: 0
p1003_1b.prioritized_io: 0
p1003_1b.priority_scheduling: 200112
p1003_1b.realtime_signals: 200112
p1003_1b.semaphores: 0
p1003_1b.fsync: 200112
p1003_1b.shared_memory_objects: 200112
p1003_1b.synchronized_io: 0
p1003_1b.timers: 200112
p1003_1b.aio_listio_max: 256
p1003_1b.aio_max: 1024
p1003_1b.aio_prio_delta_max: 0
p1003_1b.delaytimer_max: 2147483647
p1003_1b.mq_open_max: 0
p1003_1b.pagesize: 4096
p1003_1b.rtsig_max: 62
p1003_1b.sem_nsems_max: 0
p1003_1b.sem_value_max: 0
p1003_1b.sigqueue_max: 128
p1003_1b.timer_max: 32