Re: port-evbarm/54224: panic: lock error: Mutex: mutex_vector_enter,552: locking against myself

[Stephen Takacs <perlhaq%free.fr@localhost>]

The following reply was made to PR port-evbarm/54224; it has been noted by GNATS.

From: Stephen Takacs <perlhaq%free.fr@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: Nick Hudson <nick.hudson%gmx.co.uk@localhost>
Subject: Re: port-evbarm/54224: panic: lock error: Mutex: mutex_vector_enter,552:
 locking against myself
Date: Thu, 23 May 2019 22:22:47 +0200 (CEST)

 On Thu, 23 May 2019, Nick Hudson wrote:
 > uvm_fault_internal should never fault (address_exception_entry) itself -
 > this is why you trigger the KASSERT.  To debug this I'd turn on DDB and
 > UVMHIST in your kernel and when the panic triggers grab the output with
 > 'show kernhist'
 >
 > > 0x9673df44: netbsd:uvm_fault_internal+0x32c
 > > 0x9673dfac:
 >
 > Working out where this address in the code is will be useful to.  You
 > can do this with addr2line -e netbsd.gdb -f <address>, or gdb.
 
 Unfortunately, there was no netbsd.gdb file in the compile directory, and 
 neither addr2line nor gdb showed anything useful with the netbsd file. 
 But tonight I rebuilt the kernel with these extra options:
 
 # diff CUBIETRUCK.orig CUBIETRUCK
 35a36,41
 > pseudo-device cgd                     # cryptographic disk devices
 > options               UVMHIST
 > options               DDB
 > options               DDB_ONPANIC=2
 > options               DEBUG
 > makeoptions   DEBUG="-g"
 
 So it's ready for the next time this happens...