From: Mario Limonciello <mario.limonciello@amd.com>
Date: Tue, 5 Nov 2024 16:02:34 +0000 (-0600)
Subject: x86/CPU/AMD: Clear virtualized VMLOAD/VMSAVE on Zen4 client
X-Git-Tag: v6.12~1^2~2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a5ca1dc46a6b610dd4627d8b633d6c84f9724ef0;p=platform%2Fkernel%2Flinux-amlogic.git

x86/CPU/AMD: Clear virtualized VMLOAD/VMSAVE on Zen4 client

A number of Zen4 client SoCs advertise the ability to use virtualized
VMLOAD/VMSAVE, but using these instructions is reported to be a cause
of a random host reboot.

These instructions aren't intended to be advertised on Zen4 client
so clear the capability.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219009
---

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index fab5caec0b72..823f44f7bc94 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -924,6 +924,17 @@ static void init_amd_zen4(struct cpuinfo_x86 *c)
 {
 	if (!cpu_has(c, X86_FEATURE_HYPERVISOR))
 		msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT);
+
+	/*
+	 * These Zen4 SoCs advertise support for virtualized VMLOAD/VMSAVE
+	 * in some BIOS versions but they can lead to random host reboots.
+	 */
+	switch (c->x86_model) {
+	case 0x18 ... 0x1f:
+	case 0x60 ... 0x7f:
+		clear_cpu_cap(c, X86_FEATURE_V_VMSAVE_VMLOAD);
+		break;
+	}
 }
 
 static void init_amd_zen5(struct cpuinfo_x86 *c)