From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
do_not_expect_pk_fault() is a helper that we call when we do not expect
a PK fault to have occurred. But, it is a function, which means that
it obscures the line numbers from pkey_assert(). It also gives no
details.
Replace it with an implementation that gives nice line numbers and
also lets callers pass in a more descriptive message about what
happened that caused the unexpected fault.
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Ram Pai <linuxram@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
Cc: Michael Ellermen <mpe@xxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
---
b/tools/testing/selftests/x86/protection_keys.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff -puN tools/testing/selftests/x86/protection_keys.c~pkeys-selftests-give-better-pkey-fault-errors tools/testing/selftests/x86/protection_keys.c
--- a/tools/testing/selftests/x86/protection_keys.c~pkeys-selftests-give-better-pkey-fault-errors 2018-05-09 09:20:18.202698408 -0700
+++ b/tools/testing/selftests/x86/protection_keys.c 2018-05-09 09:20:18.205698408 -0700
@@ -939,10 +939,11 @@ void expected_pk_fault(int pkey)
last_si_pkey = -1;
}
-void do_not_expect_pk_fault(void)
-{
- pkey_assert(last_pkru_faults == pkru_faults);
-}
+#define do_not_expect_pk_fault(msg) do { \
+ if (last_pkru_faults != pkru_faults) \
+ dprintf0("unexpected PK fault: %s\n", msg); \
+ pkey_assert(last_pkru_faults == pkru_faults); \
+} while (0)
int test_fds[10] = { -1 };
int nr_test_fds;
@@ -1228,7 +1229,7 @@ void test_ptrace_of_child(int *ptr, u16
pkey_assert(ret != -1);
/* Now access from the current task, and expect NO exception: */
peek_result = read_ptr(plain_ptr);
- do_not_expect_pk_fault();
+ do_not_expect_pk_fault("read plain pointer after ptrace");
ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0);
pkey_assert(ret != -1);
@@ -1272,7 +1273,7 @@ void test_executing_on_unreadable_memory
*/
madvise(p1, PAGE_SIZE, MADV_DONTNEED);
lots_o_noops_around_write(&scratch);
- do_not_expect_pk_fault();
+ do_not_expect_pk_fault("executing on PROT_EXEC memory");
ptr_contents = read_ptr(p1);
dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
expected_pk_fault(pkey);
_
