[PATCH V9 20/45] mm/pkeys: PKS testing, add a fault call back

[ira . weiny]

From: Ira Weiny <ira.weiny@xxxxxxxxx>

PKS testing will need to know when a fault occurs due to it's actions so
that it can properly determine functionality.

Install a PKS fault handler for the PKS test pkey.

Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>

---
Changes for V9
	New Patch
---
 arch/x86/mm/pkeys.c | 6 +++++-
 include/linux/pks.h | 7 +++++++
 lib/pks/pks_test.c  | 6 ++++++
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c
index a3b27b7811da..39867d39460b 100644
--- a/arch/x86/mm/pkeys.c
+++ b/arch/x86/mm/pkeys.c
@@ -243,7 +243,11 @@ static DEFINE_PER_CPU(u32, pkrs_cache);
  *	#endif
  *	};
  */
-static const pks_key_callback pks_key_callbacks[PKS_KEY_MAX] = { 0 };
+static const pks_key_callback pks_key_callbacks[PKS_KEY_MAX] = {
+#ifdef CONFIG_PKS_TEST
+	[PKS_KEY_TEST]		= pks_test_fault_callback,
+#endif
+};
 
 static bool pks_call_fault_callback(struct pt_regs *regs, unsigned long address,
 				    bool write, u16 key)
diff --git a/include/linux/pks.h b/include/linux/pks.h
index d0d8bf1aaa1d..208f88fcb48c 100644
--- a/include/linux/pks.h
+++ b/include/linux/pks.h
@@ -44,4 +44,11 @@ static inline void pks_set_readwrite(u8 pkey) {}
 
 #endif /* CONFIG_ARCH_ENABLE_SUPERVISOR_PKEYS */
 
+#ifdef CONFIG_PKS_TEST
+
+bool pks_test_fault_callback(struct pt_regs *regs, unsigned long address,
+			     bool write);
+
+#endif /* CONFIG_PKS_TEST */
+
 #endif /* _LINUX_PKS_H */
diff --git a/lib/pks/pks_test.c b/lib/pks/pks_test.c
index 2fc92aaa54e8..37f2cd7d0f56 100644
--- a/lib/pks/pks_test.c
+++ b/lib/pks/pks_test.c
@@ -85,6 +85,12 @@ static void debug_result(const char *label, int test_num,
 		     sd->last_test_pass ? "PASS" : "FAIL");
 }
 
+bool pks_test_fault_callback(struct pt_regs *regs, unsigned long address,
+			     bool write)
+{
+	return false;
+}
+
 static void *alloc_test_page(u8 pkey)
 {
 	return __vmalloc_node_range(PKS_TEST_MEM_SIZE, 1, VMALLOC_START,
-- 
2.35.1