From: Martin Pieuchot <mpi@grenadille.net>
Subject: Re: VMMAP_DEBUG fix
To: David Higgs <higgsd@gmail.com>
Cc: OpenBSD Tech <tech@openbsd.org>
Date: Mon, 10 Mar 2025 20:20:24 +0100

Hello David,

On 19/02/25(Wed) 21:11, David Higgs wrote:
> Is it possible that VMMAP_DEBUG is never enabled?  I think I found a
> bug in vmspace_validate that panics because it ignores anon mmap pages
> rather than counting them.

VMMAP_DEBUG is indeed only enabled by people that hack on the code.

I applied your diff, which fix the first panic, and now I get the following,
 did you see it as well?  Do you have a fix?

panic: uvm_tree_sanity 0xfffffd800780a720 (/sys/uvm/uvm_map.c 2504): (iter->ety
pe & UVM_ET_FREEMAPPED) == 0
Stopped at      db_enter+0x14:  popq    %rbp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*381413  34081      0     0x14000      0x200    0  reaper
db_enter() at db_enter+0x14
panic(ffffffff81d9b559) at panic+0xdd
uvm_tree_sanity(fffffd800780a720,ffffffff81d1062e,9c8) at uvm_tree_sanity+0x428

vm_map_unlock_ln(fffffd800780a720,ffffffff81d1062e,9c8) at vm_map_unlock_ln+0x4
5
uvm_map_teardown(fffffd800780a720) at uvm_map_teardown+0x231
uvmspace_free(fffffd800780a720) at uvmspace_free+0x5b
reaper(ffff8000fffff480) at reaper+0x198