kselftest/arm64: Fix enumeration of systems without 128 bit SME

The current signal handling tests for SME do not account for the fact that
unlike SVE all SME vector lengths are optional so we can't guarantee that
we will encounter the minimum possible VL, they will hang enumerating VLs
on such systems. Abort enumeration when we find the lowest VL.

Fixes: 4963aeb35a9e ("kselftest/arm64: signal: Add SME signal handling tests")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230131-arm64-kselftest-sig-sme-no-128-v1-1-d47c13dc8e1e@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/tools/testing/selftests/arm64/signal/testcases/ssve_regs.c b/tools/testing/selftests/arm64/signal/testcases/ssve_regs.c
index d0eceea920736c3db9db0a18345d59c64ab4e743..3d37daafcff5131e722c8d30f9e3c144f8346855 100644 (file)
--- a/tools/testing/selftests/arm64/signal/testcases/ssve_regs.c
+++ b/tools/testing/selftests/arm64/signal/testcases/ssve_regs.c
@@ -34,6 +34,10 @@ static bool sme_get_vls(struct tdescr *td)
 
                vl &= PR_SME_VL_LEN_MASK;
 
+               /* Did we find the lowest supported VL? */
+               if (vq < sve_vq_from_vl(vl))
+                       break;
+
                /* Skip missing VLs */
                vq = sve_vq_from_vl(vl);
 

diff --git a/tools/testing/selftests/arm64/signal/testcases/za_regs.c b/tools/testing/selftests/arm64/signal/testcases/za_regs.c
index ea45acb115d5b2338c31f62d37b39e5e6475a7ac..174ad665669647042e4dc7e040ec8d852b55cd62 100644 (file)
--- a/tools/testing/selftests/arm64/signal/testcases/za_regs.c
+++ b/tools/testing/selftests/arm64/signal/testcases/za_regs.c
@@ -34,6 +34,10 @@ static bool sme_get_vls(struct tdescr *td)
 
                vl &= PR_SME_VL_LEN_MASK;
 
+               /* Did we find the lowest supported VL? */
+               if (vq < sve_vq_from_vl(vl))
+                       break;
+
                /* Skip missing VLs */
                vq = sve_vq_from_vl(vl);