pkey subsystem is supported if the hardware and kernel has support.
We determine that by checking if allocation of a key succeeds or not.
cc: Dave Hansen <dave.han...@intel.com>
cc: Florian Weimer <fwei...@redhat.com>
Signed-off-by: Ram Pai <linux...@us.ibm.com>
---
tools/testing/selftests/vm/pkey-helpers.h | 2 ++
tools/testing/selftests/vm/pkey-powerpc.h | 14 ++++++++++++--
tools/testing/selftests/vm/pkey-x86.h | 8 ++++----
tools/testing/selftests/vm/protection_keys.c | 9 +++++----
4 files changed, 23 insertions(+), 10 deletions(-)
diff --git a/tools/testing/selftests/vm/pkey-helpers.h
b/tools/testing/selftests/vm/pkey-helpers.h
index 321bbbd..288ccff 100644
--- a/tools/testing/selftests/vm/pkey-helpers.h
+++ b/tools/testing/selftests/vm/pkey-helpers.h
@@ -76,6 +76,8 @@ static inline void sigsafe_printf(const char *format, ...)
__attribute__((noinline)) int read_ptr(int *ptr);
void expected_pkey_fault(int pkey);
+int sys_pkey_alloc(unsigned long flags, u64 init_val);
+int sys_pkey_free(unsigned long pkey);
#if defined(__i386__) || defined(__x86_64__) /* arch */
#include "pkey-x86.h"
diff --git a/tools/testing/selftests/vm/pkey-powerpc.h
b/tools/testing/selftests/vm/pkey-powerpc.h
index ec6f5d7..957f6f6 100644
--- a/tools/testing/selftests/vm/pkey-powerpc.h
+++ b/tools/testing/selftests/vm/pkey-powerpc.h
@@ -62,9 +62,19 @@ static inline void __write_pkey_reg(pkey_reg_t pkey_reg)
pkey_reg);
}
-static inline int cpu_has_pku(void)
+static inline bool is_pkey_supported(void)
{
- return 1;
+ /*
+ * No simple way to determine this.
+ * Lets try allocating a key and see if it succeeds.
+ */
+ int ret = sys_pkey_alloc(0, 0);
+
+ if (ret > 0) {
+ sys_pkey_free(ret);
+ return true;
+ }
+ return false;
}
static inline int arch_reserved_keys(void)
diff --git a/tools/testing/selftests/vm/pkey-x86.h
b/tools/testing/selftests/vm/pkey-x86.h
index 95ee952..6820c10 100644
--- a/tools/testing/selftests/vm/pkey-x86.h
+++ b/tools/testing/selftests/vm/pkey-x86.h
@@ -105,7 +105,7 @@ static inline void __cpuid(unsigned int *eax, unsigned int
*ebx,
#define X86_FEATURE_PKU (1<<3) /* Protection Keys for Userspace */
#define X86_FEATURE_OSPKE (1<<4) /* OS Protection Keys Enable */
-static inline int cpu_has_pku(void)
+static inline bool is_pkey_supported(void)
{
unsigned int eax;
unsigned int ebx;
@@ -118,13 +118,13 @@ static inline int cpu_has_pku(void)
if (!(ecx & X86_FEATURE_PKU)) {
dprintf2("cpu does not have PKU\n");
- return 0;
+ return false;
}
if (!(ecx & X86_FEATURE_OSPKE)) {
dprintf2("cpu does not have OSPKE\n");
- return 0;
+ return false;
}
- return 1;
+ return true;
}
#define XSTATE_PKEY_BIT (9)
diff --git a/tools/testing/selftests/vm/protection_keys.c
b/tools/testing/selftests/vm/protection_keys.c
index ba184ca..cb81a47 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -1393,8 +1393,8 @@ void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16
pkey)
int size = PAGE_SIZE;
int sret;
- if (cpu_has_pku()) {
- dprintf1("SKIP: %s: no CPU support\n", __func__);
+ if (is_pkey_supported()) {
+ dprintf1("SKIP: %s: no CPU/kernel support\n", __func__);
return;
}
@@ -1458,12 +1458,13 @@ void run_tests_once(void)
int main(void)
{
int nr_iterations = 22;
+ int pkey_supported = is_pkey_supported();
setup_handlers();
- printf("has pkey: %d\n", cpu_has_pku());
+ printf("has pkey: %s\n", pkey_supported ? "Yes" : "No");
- if (!cpu_has_pku()) {
+ if (!pkey_supported) {
int size = PAGE_SIZE;
int *ptr;
--
1.7.1
