Please pull powerpc.git merge branch

[Paul Mackerras]

Kumar Gala writes:

> Should this also go to -stable?

It turns out that it's not triggerable (as an oops) from userspace in
2.6.22 and earlier.  Commit 1b6610d6 of Ben H's took out #ifdef
CONFIG_PPC32 around a couple of CHECK_FULL_REGS calls, which is what
made it triggerable on ppc64.  We have an interesting difference
between ppc32 and ppc64 in our CHECK_FULL_REGS implementation - it's a
BUG_ON on 64-bit but just a printk on 32-bit.  So on 32-bit someone
could use it to spam the logs but not to actually crash the system.

So yes, I guess it should go to -stable once Linus takes it, but it's
a much less serious vulnerability in 2.6.22 and earlier than I first
thought (since it's only 32-bit, and just a user-triggerable printk).

And yes we should consolidate the CHECK_FULL_REGS implementations as a
WARN_ON with a counter to limit how many we do.

Paul.