We should use perf_sample_data_init() to initialize struct
perf_sample_data.  As explained in the description of commit dc1d628a
("perf: Provide generic perf_sample_data initialization"), it is
possible for userspace to get the kernel to dereference data.raw,
so if it is not initialized, that means that unprivileged userspace
can possibly oops the kernel.  Using perf_sample_data_init makes sure
it gets initialized to NULL.

This conversion should have been included in commit dc1d628a, but it
got missed.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

Oooops... we missed these. We incorrectly converted strings
used when parsing the device-tree on pseries, thus breaking
access to drconf memory and hotplug memory.

While at it, also revert some variable names that represent
something the FW calls "lmb" and thus don't need to be converted
to "memblock".

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

This adds some debug output to our MMU hash code to print out some
useful debug data if the hypervisor refuses the insertion (which
should normally never happen).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

There's a couple of nasty bugs lurking in our huge page hashing code.

First, we don't check the access permission atomically with setting
the _PAGE_BUSY bit, which means that the PTE value we end up using
for the hashing might be different than the one we have checked
the access permissions for.

We've seen cases where that leads us to try to use an invalidated
PTE for hashing, causing all sort of "interesting" issues.

Then, we also failed to set _PAGE_DIRTY on a write access.

Finally, a minor tweak but we should return 0 when we find the
PTE busy, in order to just re-execute the access, rather than 1
which means going to do_page_fault().

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

Instead of adding _PAGE_PRESENT to the access permission mask
in each low level routine independently, we add it once from
hash_page().

We also move the preliminary access check (the racy one before
the PTE is locked) up so it applies to the huge page case. This
duplicates code in __hash_page_huge() which we'll remove in a
subsequent patch to fix a race in there.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

If the hypervisor gives us an error on a hugepage insert we panic. The
normal page code already handles this by returning an error instead and we end
calling low_hash_fault which will just kill the task if possible.

The patch below does a similar thing for the hugepage case.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The KEXEC_*_MEMORY_LIMITs are inclusive addresses.  We define them as
2Gs as that is what we allow mapping via TLBs.  However, this should be
2G - 1 to be inclusive, otherwise if we have >2G of memory in a system
we fail to boot properly via kexec.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

* 'lmb-to-memblock' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  lmb: rename to memblock

via following scripts

      FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')

      sed -i \
        -e 's/lmb/memblock/g' \
        -e 's/LMB/MEMBLOCK/g' \
        $FILES

      for N in $(find . -name lmb.[ch]); do
        M=$(echo $N | sed 's/lmb/memblock/g')
        mv $N $M
      done

and remove some wrong change like lmbench and dlmb etc.

also move memblock.c from lib/ to mm/

Suggested-by: Ingo Molnar <mingo@elte.hu>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>