powerpc: Re-enable ARCH_ENABLE_SPLIT_PMD_PTLOCK

commit 310d2e83cb9b7f1e7232319880e3fcb57592fa10 upstream.

Commit 66f24fa766e3 ("mm: drop redundant ARCH_ENABLE_SPLIT_PMD_PTLOCK")
broke PMD split page table lock for powerpc.

It selects the non-existent config ARCH_ENABLE_PMD_SPLIT_PTLOCK in
arch/powerpc/platforms/Kconfig.cputype, but clearly intended to
select ARCH_ENABLE_SPLIT_PMD_PTLOCK (notice the word swapping!), as
that commit did for all other architectures.

Fix it by selecting the correct symbol ARCH_ENABLE_SPLIT_PMD_PTLOCK.

Fixes: 66f24fa766e3 ("mm: drop redundant ARCH_ENABLE_SPLIT_PMD_PTLOCK")
Cc: stable@vger.kernel.org # v5.13+
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
[mpe: Reword change log to make it clear this is a bug fix]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210819113954.17515-3-lukas.bulwahn@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index f998e655b5706c8511e02f15deda0d4f26dba06d..7450651a753616fae8786c28978022921a3f370b 100644 (file)
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -97,7 +97,7 @@ config PPC_BOOK3S_64
        select PPC_HAVE_PMU_SUPPORT
        select HAVE_ARCH_TRANSPARENT_HUGEPAGE
        select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
-       select ARCH_ENABLE_PMD_SPLIT_PTLOCK
+       select ARCH_ENABLE_SPLIT_PMD_PTLOCK
        select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
        select ARCH_SUPPORTS_HUGETLBFS
        select ARCH_SUPPORTS_NUMA_BALANCING