The BTI selftests are built both with and without BTI support, validating both the generation of BTI signals as expected for binaries without BTI support. Both versions of the binary currently skip all their tests when the system does not support BTI, however this is excessive since we do have a defined ABI for how the programs should function in this case (especially for the non-BTI binary). Update the test program to run all the tests unconditionally, adding a runtime adjustment of the expected results on systems that don't support BTI where we currently handle the build time case.
The tests all use HINT space instructions, BTI itself is a HINT as is are the PAC instructions that function as landing pads, so nothing in the tests depends on support for BTI in the kernel or hardware.
Signed-off-by: Mark Brown broonie@kernel.org --- tools/testing/selftests/arm64/bti/test.c | 25 ++++++++++--------------- 1 file changed, 10 insertions(+), 15 deletions(-)
diff --git a/tools/testing/selftests/arm64/bti/test.c b/tools/testing/selftests/arm64/bti/test.c index 4b6dda987c58..2cd8dcee5aec 100644 --- a/tools/testing/selftests/arm64/bti/test.c +++ b/tools/testing/selftests/arm64/bti/test.c @@ -6,6 +6,7 @@
#include "system.h"
+#include <stdbool.h> #include <stddef.h> #include <linux/errno.h> #include <linux/auxvec.h> @@ -101,7 +102,8 @@ static void handler(int n, siginfo_t *si __always_unused, uc->uc_mcontext.pstate &= ~PSR_BTYPE_MASK; }
-static int skip_all; +/* Does the system have BTI? */ +static bool have_bti;
static void __do_test(void (*trampoline)(void (*)(void)), void (*fn)(void), @@ -109,19 +111,11 @@ static void __do_test(void (*trampoline)(void (*)(void)), const char *name, int expect_sigill) { - if (skip_all) { - test_skipped++; - putstr("ok "); - putnum(test_num++); - putstr(" "); - puttestname(name, trampoline_name); - putstr(" # SKIP\n"); - - return; - } - - /* Branch Target exceptions should only happen in BTI binaries: */ - if (!BTI) + /* + * Branch Target exceptions should only happen for BTI + * binaries running on a system with BTI: + */ + if (!BTI || !have_bti) expect_sigill = 0;
sigill_expected = expect_sigill; @@ -199,9 +193,10 @@ void start(int *argcp) putstr("# HWCAP2_BTI present\n"); if (!(hwcap & HWCAP_PACA)) putstr("# Bad hardware? Expect problems.\n"); + have_bti = true; } else { putstr("# HWCAP2_BTI not present\n"); - skip_all = 1; + have_bti = false; }
putstr("# Test binary");