4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Michael Ellerman <m...@ellerman.id.au>

commit 7ece370996b694ae263025e056ad785afc1be5ab upstream.

Currently userspace is able to request mmap() search between 128T-512T
by specifying a hint address that is greater than 128T. But that means
a hint of 128T exactly will return an address below 128T, which is
confusing and wrong.

So fix the logic to check the hint is greater than *or equal* to 128T.

Fixes: f4ea6dcb08ea ("powerpc/mm: Enable mappings above 128TB")
Suggested-by: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
Suggested-by: Nicholas Piggin <npig...@gmail.com>
[mpe: Split out of Nick's bigger patch]
Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 arch/powerpc/mm/slice.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -419,7 +419,7 @@ unsigned long slice_get_unmapped_area(un
        /*
         * Check if we need to expland slice area.
         */
-       if (unlikely(addr > mm->context.addr_limit &&
+       if (unlikely(addr >= mm->context.addr_limit &&
                     mm->context.addr_limit != TASK_SIZE)) {
                mm->context.addr_limit = TASK_SIZE;
                on_each_cpu(slice_flush_segments, mm, 1);
@@ -427,7 +427,7 @@ unsigned long slice_get_unmapped_area(un
        /*
         * This mmap request can allocate upt to 512TB
         */
-       if (addr > DEFAULT_MAP_WINDOW)
+       if (addr >= DEFAULT_MAP_WINDOW)
                high_limit = mm->context.addr_limit;
        else
                high_limit = DEFAULT_MAP_WINDOW;


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