DF-2903 fixed-kernel validation (after fix.diff, kernel #1)
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Command: vnconfig -c -v -S 512 vn0 /root/ontrack.img   (same md5 image)
Kernel:  DragonFly 6.5-DEVELOPMENT #1 (patched, built in-guest make nativekernel)

/dev/vn0: /root/ontrack.img, 131072 bytes mapped
ONTRACK_RC=0
/dev/vn0
/dev/vn0s1

=> No panic; attach completes; the slice table re-read at LBA 63 is parsed
   normally (/dev/vn0s1 created); guest stays up. Baseline panic is GONE.