4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
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.kumar@xxxxxxxxxxxxxxxxxx>
Suggested-by: Nicholas Piggin <npiggin@xxxxxxxxx>
[mpe: Split out of Nick's bigger patch]
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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;