From 3c42e9542050d49610077e083c7c3f5fd5e26820 Mon Sep 17 00:00:00 2001
From: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Date: Tue, 7 Dec 2021 10:05:57 -0300
Subject: [PATCH] selftests/powerpc/spectre_v2: Return skip code when miss_percent is high
Git-commit: 3c42e9542050d49610077e083c7c3f5fd5e26820
Patch-mainline: v5.17-rc1
References: git-fixes

A mis-match between reported and actual mitigation is not restricted to the
Vulnerable case. The guest might also report the mitigation as "Software
count cache flush" and the host will still mitigate with branch cache
disabled.

So, instead of skipping depending on the detected mitigation, simply skip
whenever the detected miss_percent is the expected one for a fully
mitigated system, that is, above 95%.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211207130557.40566-1-cascardo@canonical.com
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 tools/testing/selftests/powerpc/security/spectre_v2.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/powerpc/security/spectre_v2.c b/tools/testing/selftests/powerpc/security/spectre_v2.c
index adc2b7294e5f..83647b8277e7 100644
--- a/tools/testing/selftests/powerpc/security/spectre_v2.c
+++ b/tools/testing/selftests/powerpc/security/spectre_v2.c
@@ -193,7 +193,7 @@ int spectre_v2_test(void)
 			 * We are not vulnerable and reporting otherwise, so
 			 * missing such a mismatch is safe.
 			 */
-			if (state == VULNERABLE)
+			if (miss_percent > 95)
 				return 4;
 
 			return 1;
-- 
2.35.3