From: Mark Brown <broonie@kernel.org>
Date: Tue, 27 Dec 2022 13:06:35 +0000
Subject: [PATCH] kselftest/arm64: Fix syscall-abi for systems without 128 bit
 SME
References: bsc#1012628
Patch-mainline: 6.2.3
Git-commit: 97ec597b26df774a257e3f8e97353fd1b4471615

[ Upstream commit 97ec597b26df774a257e3f8e97353fd1b4471615 ]

SME does not mandate any specific VL so we may not have 128 bit SME but
the algorithm used for enumerating VLs assumes that we will. Add the
required check to ensure that the algorithm terminates.

Fixes: 43e3f85523e4 ("kselftest/arm64: Add SME support to syscall ABI test")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221223-arm64-syscall-abi-sme-only-v1-1-4fabfbd62087@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 tools/testing/selftests/arm64/abi/syscall-abi.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/testing/selftests/arm64/abi/syscall-abi.c b/tools/testing/selftests/arm64/abi/syscall-abi.c
index dd7ebe53..ffe719b5 100644
--- a/tools/testing/selftests/arm64/abi/syscall-abi.c
+++ b/tools/testing/selftests/arm64/abi/syscall-abi.c
@@ -390,6 +390,10 @@ static void test_one_syscall(struct syscall_cfg *cfg)
 
 			sme_vl &= PR_SME_VL_LEN_MASK;
 
+			/* Found lowest VL */
+			if (sve_vq_from_vl(sme_vl) > sme_vq)
+				break;
+
 			if (sme_vq != sve_vq_from_vl(sme_vl))
 				sme_vq = sve_vq_from_vl(sme_vl);
 
@@ -461,6 +465,10 @@ int sme_count_vls(void)
 
 		vl &= PR_SME_VL_LEN_MASK;
 
+		/* Found lowest VL */
+		if (sve_vq_from_vl(vl) > vq)
+			break;
+
 		if (vq != sve_vq_from_vl(vl))
 			vq = sve_vq_from_vl(vl);
 
-- 
2.35.3