# DF-2632 environment (audit guest, single-tenant QEMU/KVM)

## stock kernel (baseline reproduction)
DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #0: Thu Jul  2 06:02:54 UTC 2026  root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64
kern.osrevision: 600519
cc 8.3 [DragonFly] Release/2019-02-22
kern.clockrate: { hz = 100, tick = 10000 }
hw.usermem: 3754377216
vCPUs: 6 (KVM), /tmp tmpfs ~975M, root vbd0s1d hammer2
/usr/src verified pristine (md5 hammer2_chain.c e2656e57dfa6189a58ddbdf59e1ece0e == audit tree)

## fix kernel (validation)
DragonFly 6.5-DEVELOPMENT #2: Sat Aug 29 08:00:46 UTC 2026 root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC
= X86_64_GENERIC (identical config incl. INVARIANTS) + fix.diff
build: cd /usr/src && make -j6 nativekernel KERNCONF=X86_64_GENERIC && make installkernel KERNCONF=X86_64_GENERIC
(compiled clean under -Werror; an intermediate kernel #1 carrying only the
 mid-loop defer variant tripped KKASSERT chain->core.live_count==0 in
 hammer2_chain_repchange (chain.c:2314) — see VERDICT.md "iteration 1";
 final kernel #2 adds the pre-flight collapse abort and validates clean)

## test filesystems
- /dev/vn1@DATA hammer2 512MB on /mnt/h2632 (vn over /tmp tmpfs image)
- 256MB variant for the natural-name probe, 64MB for roundtrips