Linux 6.6.26

[thirdparty/kernel/stable-queue.git] / releases / 6.6.26 / x86-cpu-amd-carve-out-the-erratum-1386-fix.patch

From 6fa756f7aa84827d2e839b8a1ef4360092ecf23d Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Wed, 1 Nov 2023 11:14:59 +0100
Subject: x86/CPU/AMD: Carve out the erratum 1386 fix

From: Borislav Petkov (AMD) <bp@alien8.de>

[ Upstream commit a7c32a1ae9ee43abfe884f5af376877c4301d166 ]

Call it on the affected CPU generations.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Link: http://lore.kernel.org/r/20231120104152.13740-3-bp@alien8.de
Stable-dep-of: c7b2edd8377b ("perf/x86/amd/core: Update and fix stalled-cycles-* events for Zen 2 and later")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/x86/kernel/cpu/amd.c | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 5391385707b3f..28c3a1045b060 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -988,6 +988,19 @@ static void init_amd_bd(struct cpuinfo_x86 *c)
 	clear_rdrand_cpuid_bit(c);
 }
 
+static void fix_erratum_1386(struct cpuinfo_x86 *c)
+{
+	/*
+	 * Work around Erratum 1386.  The XSAVES instruction malfunctions in
+	 * certain circumstances on Zen1/2 uarch, and not all parts have had
+	 * updated microcode at the time of writing (March 2023).
+	 *
+	 * Affected parts all have no supervisor XSAVE states, meaning that
+	 * the XSAVEC instruction (which works fine) is equivalent.
+	 */
+	clear_cpu_cap(c, X86_FEATURE_XSAVES);
+}
+
 void init_spectral_chicken(struct cpuinfo_x86 *c)
 {
 #ifdef CONFIG_CPU_UNRET_ENTRY
@@ -1008,15 +1021,6 @@ void init_spectral_chicken(struct cpuinfo_x86 *c)
 		}
 	}
 #endif
-	/*
-	 * Work around Erratum 1386.  The XSAVES instruction malfunctions in
-	 * certain circumstances on Zen1/2 uarch, and not all parts have had
-	 * updated microcode at the time of writing (March 2023).
-	 *
-	 * Affected parts all have no supervisor XSAVE states, meaning that
-	 * the XSAVEC instruction (which works fine) is equivalent.
-	 */
-	clear_cpu_cap(c, X86_FEATURE_XSAVES);
 }
 
 static void init_amd_zn(struct cpuinfo_x86 *c)
@@ -1085,10 +1089,12 @@ static void zenbleed_check(struct cpuinfo_x86 *c)
 
 static void init_amd_zen(struct cpuinfo_x86 *c)
 {
+	fix_erratum_1386(c);
 }
 
 static void init_amd_zen2(struct cpuinfo_x86 *c)
 {
+	fix_erratum_1386(c);
 }
 
 static void init_amd_zen3(struct cpuinfo_x86 *c)
-- 
2.43.0