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

JIRA: https://issues.redhat.com/browse/RHEL-67470
CVE: CVE-2024-53114
Upstream: Merged

commit a5ca1dc
Author: Mario Limonciello <[email protected]>
Date:   Tue Nov 5 10:02:34 2024 -0600

    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 <[email protected]>
    Signed-off-by: Borislav Petkov (AMD) <[email protected]>
    Cc: [email protected]
    Link: https://bugzilla.kernel.org/show_bug.cgi?id=219009

Signed-off-by: Jon Maloy <[email protected]>

Author: lmcjoma

arch/x86/kernel/cpu/amd.c

@@ -912,6 +912,17 @@ 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)