mdadm raid1 stops to work after kernel panic

[Federico <undicizeri@gmail.com>]

Accidentally I've booted with wrong grub parameters and my systems
hanged with a kernel panic. After reboot my /dev/md2 device (raid1)
stopped to work.
These are some logs:

wax@persifae:~$cat /proc/mdstat
Personalities : [raid1]
md2 : inactive sda1[0](S)
      293049600 blocks

md1 : active raid1 sdc6[0] sdb2[1]
      152264000 blocks [2/2] [UU]

md0 : active raid1 sdb1[1] sdc5[0]
      7815488 blocks [2/2] [UU]

unused devices: <none>

wax@persifae:~$sudo mdadm -Q /dev/md2
/dev/md2: is an md device which is not active

wax@persifae:~$sudo mdadm --assemble --scan /dev/md2
mdadm: failed to add /dev/sdc1 to /dev/md2: Invalid argument
mdadm: /dev/md2 assembled from 0 drives - not enough to start the array.

wax@persifae:~$cat /etc/mdadm.conf
ARRAY /dev/md0 level=raid1 num-devices=2
UUID=2a37b0a1:4b6b28fc:0209446b:c3b28f2a
ARRAY /dev/md1 level=raid1 num-devices=2
UUID=19c49c5d:e3193aa1:657f267b:b23c2dee
ARRAY /dev/md2 level=raid1 num-devices=2
UUID=62a5cb51:36ca61a3:1298e6c2:30fde3ba

Thanks in advance for your help