Alt-SysRq-B doesn't work in recent 2.6 kernels

Alt-SysRq-B doesn't work in recent 2.6 kernels

[Alessandro Suardi]

Now that my oops-on-boot has been fixed thanks to many on lkml
  and a spot-on tip by Len Brown, I'll chase another one of the
  issues I still have :)

The problem in $subject happens reliably at least in 2 cases:

  1. after the ACPI oops-on-boot (-mm tree and 2.6.2-rc2+)
  2. in 2.6.2-rc1+ after the Cisco VPN client daemon (cvpnd,
      v.4.0.3.B) gets stuck in D state [__down] and I try to
      shutdown but obviously that gets stuck in turn

In both cases I can Alt-SysRq-{P,T,S,U,O} [though in case 1
  Off only prints out "Power Off" but doesn't actually do it],
  and when I attempt a Alt-SysRq-B I only get

atkbd.c: Keyboard on isa0060/serio0 reports too many keys pressed.

  and no effect at all.


Available for testing, as usual :) thanks in advance & ciao,

--alessandro

  "Two rivers run too deep
   The seasons change and so do I"
       (U2, "Indian Summer Sky")