[PATCH v18 09/24] selftests/vm/pkeys: Fix assertion in pkey_disable_set/clear()

Sandipan Das
2020-01-30T06:37:46Z

In some cases, a pkey's bits need not necessarily change
in a way that the value of the pkey register increases
when performing a pkey_disable_set() or decreases when
performing a pkey_disable_clear().

For example, on powerpc, if a pkey's current state is
PKEY_DISABLE_ACCESS and we perform a pkey_write_disable()
on it, the bits still remain the same. We will observe
something similar when the pkey's current state is 0 and
a pkey_access_enable() is performed on it.

Either case would cause some assertions to fail. This
fixes the problem.

cc: Dave Hansen <dave.hansen@intel.com>
cc: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
---
tools/testing/selftests/vm/protection_keys.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 4b1ddb526228..7fd52d5c4bfd 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -400,7 +400,7 @@ void pkey_disable_set(int pkey, int flags)
dprintf1("%s(%d) pkey_reg: 0x%016llx\n",
__func__, pkey, read_pkey_reg());
if (flags)
- pkey_assert(read_pkey_reg() > orig_pkey_reg);
+ pkey_assert(read_pkey_reg() >= orig_pkey_reg);
dprintf1("END<---%s(%d, 0x%x)\n", __func__,
pkey, flags);
}
@@ -431,7 +431,7 @@ void pkey_disable_clear(int pkey, int flags)
dprintf1("%s(%d) pkey_reg: 0x%016llx\n", __func__,
pkey, read_pkey_reg());
if (flags)
- assert(read_pkey_reg() < orig_pkey_reg);
+ assert(read_pkey_reg() <= orig_pkey_reg);
}

void pkey_write_allow(int pkey)
--
2.17.1