linux-kernel - [tip: x86/cpu] x86/CPU/AMD: Move the Zen3 BTC

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Date:   Wed, 29 Nov 2023 11:22:32 -0000
From:   "tip-bot2 for Borislav Petkov (AMD)" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     "Borislav Petkov (AMD)" <bp@...en8.de>,
        Nikolay Borisov <nik.borisov@...e.com>, x86@...nel.org,
        linux-kernel@...r.kernel.org
Subject: [tip: x86/cpu] x86/CPU/AMD: Move the Zen3 BTC_NO detection to the
 Zen3 init function

The following commit has been merged into the x86/cpu branch of tip:

Commit-ID:     affc66cb96f865b3763a8e18add52e133d864f04
Gitweb:        https://git.kernel.org/tip/affc66cb96f865b3763a8e18add52e133d864f04
Author:        Borislav Petkov (AMD) <bp@...en8.de>
AuthorDate:    Wed, 01 Nov 2023 11:28:31 +01:00
Committer:     Borislav Petkov (AMD) <bp@...en8.de>
CommitterDate: Wed, 29 Nov 2023 12:11:44 +01:00

x86/CPU/AMD: Move the Zen3 BTC_NO detection to the Zen3 init function

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@...en8.de>
Reviewed-by: Nikolay Borisov <nik.borisov@...e.com>
Link: http://lore.kernel.org/r/20231120104152.13740-4-bp@alien8.de
---
 arch/x86/kernel/cpu/amd.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 0a499cb..3d74347 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -1031,14 +1031,6 @@ static void init_amd_zn(struct cpuinfo_x86 *c)
 		/* Erratum 1076: CPB feature bit not being set in CPUID. */
 		if (!cpu_has(c, X86_FEATURE_CPB))
 			set_cpu_cap(c, X86_FEATURE_CPB);
-
-		/*
-		 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
-		 * Branch Type Confusion, but predate the allocation of the
-		 * BTC_NO bit.
-		 */
-		if (c->x86 == 0x19 && !cpu_has(c, X86_FEATURE_BTC_NO))
-			set_cpu_cap(c, X86_FEATURE_BTC_NO);
 	}
 }
 
@@ -1094,6 +1086,15 @@ static void init_amd_zen2(struct cpuinfo_x86 *c)
 
 static void init_amd_zen3(struct cpuinfo_x86 *c)
 {
+	if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
+		/*
+		 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
+		 * Branch Type Confusion, but predate the allocation of the
+		 * BTC_NO bit.
+		 */
+		if (!cpu_has(c, X86_FEATURE_BTC_NO))
+			set_cpu_cap(c, X86_FEATURE_BTC_NO);
+	}
 }
 
 static void init_amd_zen4(struct cpuinfo_x86 *c)