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)