[Crash-utility] kdump on x86_64 - why not discover a scsi device?

[Cliff Wickman]

Hi all,

  Can anyone tell me why a dump capture kernel cannot discover my
root device?

  I'm using an x86_64 box.
  My 2.6.16 kernel can load either a 2.6.16 or 2.6.22 capture kernel
and it can successfully find the root device.

  The system has /dev/sdba and /dev/sdb.  I'm using a root on sdb.

  But when my 2.6.22 kernel loads either a 2.6.16 or 2.6.22 capture kernel
that capture kernel cannot find /dev/sdb.

  Must be a configuration issue.
  Maybe involving some combination of CONFIG_KEXEC and CONFIG_CRASH_DUMP.
  But I don't see how those can affect disk discovery.

  Any ideas?

-Cliff