[PATCH v16 23/23] selftests: vm: pkeys: Use the correct page size on powerpc

[Sandipan Das <sandipan@linux.ibm.com>]

Both 4K and 64K pages are supported on powerpc. Parts of
the selftest code perform alignment computations based on
the PAGE_SIZE macro which is currently hardcoded to 64K
for powerpc. This causes some test failures on kernels
configured with 4K page size.

In some cases, we need to enforce function alignment to
page size. Since this can only be done at build time,
64K is used as the alignment factor as that ensures 4K
alignment as well.

cc: Dave Hansen <dave.hansen@intel.com>
cc: Florian Weimer <fweimer@redhat.com>
cc: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
---
 tools/testing/selftests/vm/pkey-powerpc.h    | 2 +-
 tools/testing/selftests/vm/protection_keys.c | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/vm/pkey-powerpc.h b/tools/testing/selftests/vm/pkey-powerpc.h
index 1753b01882a7..7435bf30298d 100644
--- a/tools/testing/selftests/vm/pkey-powerpc.h
+++ b/tools/testing/selftests/vm/pkey-powerpc.h
@@ -36,7 +36,7 @@
 					     pkey-31 and exec-only key */
 #define PKEY_BITS_PER_PKEY	2
 #define HPAGE_SIZE		(1UL << 24)
-#define PAGE_SIZE		(1UL << 16)
+#define PAGE_SIZE		sysconf(_SC_PAGESIZE)
 
 static inline u32 pkey_bit_position(int pkey)
 {
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 9e04bfbbd7e6..36fe219c8099 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -145,7 +145,12 @@ void abort_hooks(void)
  * will then fault, which makes sure that the fault code handles
  * execute-only memory properly.
  */
+#ifdef __powerpc64__
+/* This way, both 4K and 64K alignment are maintained */
+__attribute__((__aligned__(65536)))
+#else
 __attribute__((__aligned__(PAGE_SIZE)))
+#endif
 void lots_o_noops_around_write(int *write_to_me)
 {
 	dprintf3("running %s()\n", __func__);
-- 
2.17.1