[v2] powerpc: Fix checkstop in native_hpte_clear() with lockdep

[Michael Ellerman]

On Thu, 2015-08-10 at 00:04:26 UTC, Cyril Bur wrote:
> native_hpte_clear() is called in real mode from two places:
> - Early in boot during htab initialisation if firmware assisted dump is
>   active.
> - Late in the kexec path.
> 
> In both contexts there is no need to disable interrupts are they are
> already disabled. Furthermore, locking around the tlbie() is only required
> for pre POWER5 hardware.
> 
> On POWER5 or newer hardware concurrent tlbie()s work as expected and on pre
> POWER5 hardware concurrent tlbie()s could result in deadlock. This code
> would only be executed at crashdump time, during which all bets are off,
> concurrent tlbie()s are unlikely and taking locks is unsafe therefore the
> best course of action is to simply do nothing. Concurrent tlbie()s are not
> possible in the first case as secondary CPUs have not come up yet.
> 
> Signed-off-by: Cyril Bur <cyrilbur at gmail.com>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/fdf880a60835cd1dec256346

cheers