ccd, gpt and kernel panic.

[BERTRAND Joël <joel.bertrand%systella.fr@localhost>]

	Hello,

	I use for a long time a NetBSD system that acts as boot (tftpd), NFS
and iSCSI server for diskless workstations. This server tuns 9.0_STABLE :
legendre# uname -a
NetBSD legendre.systella.fr 9.0_STABLE NetBSD 9.0_STABLE (CUSTOM) #12:
Thu Oct  1 08:59:33 CEST 2020
root%legendre.systella.fr@localhost:/usr/src/netbsd-9/obj/sys/arch/amd64/compile/CUSTOM
amd64

	iSCSI was only used for swap on an old disk. When I have installed this
iSCSI server, I have created wedges on GPT labels without difficulties
(if I remember) :

#dkctl wd0 listwedges :
/dev/rwd0d: 3 wedges:
dk0: swap_hilbert, 67108864 blocks at 34, type: swap
dk1: swap_abel, 2097152 blocks at 67108898, type: swap
dk2: swap_schwarz, 33554432 blocks at 69206050, type: swap

	Now, I have replaced this old disk (SATA 3Gbps, 160 Go, 4500rpms) by
two others disks (SATA 6Gbps, 1To, 7200rpms). In a first time, I have
configured ccd :

legendre# cat /etc/ccd.conf
ccd0    32      none    /dev/wd0a /dev/wd1a
legendre# dmesg
...
[   511.661981] ccd0: Interleaving 2 components (32 block interleave)
[   511.661981] ccd0: /dev/wd0a (1953524160 blocks)
[   511.661981] ccd0: /dev/wd1a (1953524160 blocks)
[   511.661981] ccd0: total 3907048320 blocks

	If I understand, I have now a new virtual disk and I can create new
wedges on this disk. And I have tried :
legendre# gpt add -a 4k -l swap_hilbert -s 96g -t swap ccd0

	Result : kernel panics ! That's being said, last command writes
something in GPT as after a reboot, I can see :

legendre# gpt show ccd0
       start        size  index  contents
           0           1         PMBR
           1           1         Pri GPT header
           2          32         Pri GPT table
          34           6         Unused
          40   201326592      1  GPT part - NetBSD swap
   201326632  3705721655         Unused
  3907048287          32         Sec GPT table
  3907048319           1         Sec GPT header

but no wedge is created and dk1 (in my case) remains unconfigured.

	How can I create these wedges ?

	Best regards,

	JKB