Boot error after upgrade from 4.9 to 5.2

[Jeremie LE HEN]

Hi,

I have just upgraded my system from a RELENG_4 to a RELENG_5_2.  I made
everything adviced in src/UPDATING, including buildworld, buildkernel,
installkernel, reboot, installworld and when I finally rebooted to get
a runnable box, it failed between the second and the third stage of the
boot sequence :

F1  FreeBSD

Default: F1

Disk error 0x4 (lba=0x95b1c1f3)
Invalid format

>> FreeBSD/i386 BOOT
Default: 0:ad(0,a)/kernel
boot:
Disk error 0x4 (lba=0x1e27f153)
Invalid format

>> FreeBSD/i386 BOOT
Default: 0:ad(0,a)/kernel
boot:



After reading boot(8) manual page, I saw that error 0x4 means
"Sector not found", but I don't understand which sector it could not
find, since it has worked very well for a long time with 4-stable.

Advices are welcome.
Thanks in advance.

Regards,
-- 
Jeremie LE HEN aka TtZ/TataZ                          jeremie.le-hen at epita.fr
                                                                 ttz at epita.fr
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