The following commit has been merged into the x86/urgent branch of tip:
Commit-ID: a5ca1dc46a6b610dd4627d8b633d6c84f9724ef0
Gitweb: https://git.kernel.org/tip/a5ca1dc46a6b610dd4627d8b633d6c84f9724ef0
Author: Mario Limonciello <mario.limonciello@amd.com>
AuthorDate: Tue, 05 Nov 2024 10:02:34 -06:00
Committer: Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Tue, 05 Nov 2024 17:48:32 +01:00
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
---
arch/x86/kernel/cpu/amd.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index fab5cae..823f44f 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)