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From:   Nikunj A Dadhania <nikunj@amd.com>
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Subject: [RFC PATCH 10/11] x86/tsc: Mark Secure TSC as reliable clocksource
Date:   Mon, 30 Jan 2023 17:33:26 +0530
Message-ID: <20230130120327.977460-11-nikunj@amd.com>
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AMD SNP guests may have Secure TSC feature enabled. Secure TSC as
clocksource is wrongly marked as unstable, mark Secure TSC as
reliable.

Signed-off-by: Nikunj A Dadhania <nikunj@amd.com>
---
 arch/x86/kernel/tsc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index a78e73da4a74..7a7a5eaacb54 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -1200,7 +1200,7 @@ static void __init check_system_tsc_reliable(void)
 			tsc_clocksource_reliable = 1;
 	}
 #endif
-	if (boot_cpu_has(X86_FEATURE_TSC_RELIABLE))
+	if (boot_cpu_has(X86_FEATURE_TSC_RELIABLE) || cc_platform_has(CC_ATTR_GUEST_SECURE_TSC))
 		tsc_clocksource_reliable = 1;
 
 	/*
-- 
2.32.0