This is a note to let you know that I've just added the patch titled

powerpc/64s/hash: Fix 512T hint detection to use >= 128T

to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: powerpc-64s-hash-fix-512t-hint-detection-to-use-128t.patch and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 7ece370996b694ae263025e056ad785afc1be5ab Mon Sep 17 00:00:00 2001

From: Michael Ellerman mpe@ellerman.id.au Date: Mon, 13 Nov 2017 23:17:28 +1100 Subject: powerpc/64s/hash: Fix 512T hint detection to use >= 128T

From: Michael Ellerman mpe@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.kumar@linux.vnet.ibm.com Suggested-by: Nicholas Piggin npiggin@gmail.com [mpe: Split out of Nick's bigger patch] Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman gregkh@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;

Patches currently in stable-queue which might be from mpe@ellerman.id.au are

queue-4.14/powerpc-perf-imc-use-cpu_to_node-not-topology_physical_package_id.patch queue-4.14/powerpc-64s-hash-fix-128tb-512tb-virtual-address-boundary-case-allocation.patch queue-4.14/powerpc-fix-boot-on-book3s_32-with-config_strict_kernel_rwx.patch queue-4.14/powerpc-64s-hash-fix-fork-with-512tb-process-address-space.patch queue-4.14/powerpc-mm-radix-fix-crashes-on-power9-dd1-with-radix-mmu-and-strict_rwx.patch queue-4.14/powerpc-64s-radix-fix-128tb-512tb-virtual-address-boundary-case-allocation.patch queue-4.14/powerpc-signal-properly-handle-return-value-from-uprobe_deny_signal.patch queue-4.14/powerpc-64s-hash-allow-map_fixed-allocations-to-cross-128tb-boundary.patch queue-4.14/powerpc-64s-hash-fix-512t-hint-detection-to-use-128t.patch queue-4.14/powerpc-64s-fix-masking-of-srr1-bits-on-instruction-fault.patch