Running multiple Windows VMs with VP Assis and APICv causes KVM internal error on Spapphire Rpaids and Emerald Rapids as is reported in [1]. Here Qemu outputs: KVM internal error. Suberror: 3 extra data[0]: 0x000000008000002f extra data[1]: 0x0000000000000020 extra data[2]: 0x0000000000000582 extra data[3]: 0x0000000000000006 RAX=0000000000000000 RBX=0000000000000000 RCX=0000000040000070 RDX=0000000000000000 RSI=fffffa8001e3db60 RDI=fffffa8002bc8aa0 RBP=fffff88005a91670 RSP=fffff88005a915c8 R8 =0000000000000009 R9 =000000000000000b R10=fffff8000264b000 R11=fffff88005a91750 R12=fffff88002e40180 R13=fffffa8001e3dc68 R14=fffffa8001e3dc68 R15=0000000000000002 RIP=fffff8000271722c RFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0 ES =002b 0000000000000000 ffffffff 00c0f300 DPL=3 DS [-WA] CS =0010 0000000000000000 00000000 00209b00 DPL=0 CS64 [-RA] SS =0018 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA] DS =002b 0000000000000000 ffffffff 00c0f300 DPL=3 DS [-WA] FS =0053 00000000fff9a000 00007c00 0040f300 DPL=3 DS [-WA] GS =002b fffff88002e40000 ffffffff 00c0f300 DPL=3 DS [-WA] LDT=0000 0000000000000000 ffffffff 00c00000 TR =0040 fffff88002e44ec0 00000067 00008b00 DPL=0 TSS64-busy GDT= fffff88002e4b4c0 0000007f IDT= fffff88002e4b540 00000fff CR0=80050031 CR2=00000000002e408e CR3=000000001c6f5000 CR4=000406f8 DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 DR3=0000000000000000 DR6=00000000fffe07f0 DR7=0000000000000400 EFER=0000000000000d01 Code=25 a8 4b 00 00 b9 70 00 00 40 0f ba 32 00 72 06 33 c0 8b d0 <0f> 30 5a 58 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 cc cc cc cc cc cc 66 66 0f 1f As is noted in [1], this issue is considered to be a microcode issue specific to SPR/EMR. Disable APICv when guest tries to enable VP Assist page only when it's running on those problematic CPU models. Link: https://bugzilla.kernel.org/show_bug.cgi?id=218267 [1] Signed-off-by: Eiichi Tsukata <eiichi.tsukata@xxxxxxxxxxx> --- arch/x86/include/asm/kvm_host.h | 8 ++++++++ arch/x86/kvm/hyperv.c | 13 +++++++++++++ arch/x86/kvm/vmx/main.c | 1 + 3 files changed, 22 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 950a03e0181e..9ff687c7326b 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1213,6 +1213,13 @@ enum kvm_apicv_inhibit { */ APICV_INHIBIT_REASON_HYPERV, + /* + * Using VP Assist and APICv simultaneously on Sapphire Rapids + * or Emerald Rapids causes KVM internal error, which is + * considered to be a microcode issue. + */ + APICV_INHIBIT_REASON_HYPERV_VP_ASSIST, + /* * APIC acceleration is inhibited because the userspace didn't yet * enable the kernel/split irqchip. @@ -1285,6 +1292,7 @@ enum kvm_apicv_inhibit { #define APICV_INHIBIT_REASONS \ __APICV_INHIBIT_REASON(DISABLED), \ __APICV_INHIBIT_REASON(HYPERV), \ + __APICV_INHIBIT_REASON(HYPERV_VP_ASSIST), \ __APICV_INHIBIT_REASON(ABSENT), \ __APICV_INHIBIT_REASON(BLOCKIRQ), \ __APICV_INHIBIT_REASON(PHYSICAL_ID_ALIASED), \ diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 4f0a94346d00..8d5a1f685191 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -36,6 +36,7 @@ #include <asm/apicdef.h> #include <asm/mshyperv.h> +#include <asm/cpu_device_id.h> #include <trace/events/kvm.h> #include "trace.h" @@ -1550,6 +1551,8 @@ static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host) case HV_X64_MSR_VP_ASSIST_PAGE: { u64 gfn; unsigned long addr; + struct kvm *kvm = vcpu->kvm; + struct cpuinfo_x86 *c = &boot_cpu_data; if (!(data & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) { hv_vcpu->hv_vapic = data; @@ -1571,6 +1574,16 @@ static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host) return 1; hv_vcpu->hv_vapic = data; kvm_vcpu_mark_page_dirty(vcpu, gfn); + + /* + * Using VP Assist and APICv simultaneously on Sapphire Rapids + * or Emerald Rapids causes KVM internal error, which is + * considered to be a microcode issue. + */ + if (c->x86_vfm == INTEL_SAPPHIRERAPIDS_X || + c->x86_vfm == INTEL_EMERALDRAPIDS_X) + kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_HYPERV_VP_ASSIST); + if (kvm_lapic_set_pv_eoi(vcpu, gfn_to_gpa(gfn) | KVM_MSR_ENABLED, sizeof(struct hv_vp_assist_page))) diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c index 0bf35ebe8a1b..a1e7007133a1 100644 --- a/arch/x86/kvm/vmx/main.c +++ b/arch/x86/kvm/vmx/main.c @@ -11,6 +11,7 @@ (BIT(APICV_INHIBIT_REASON_DISABLED) | \ BIT(APICV_INHIBIT_REASON_ABSENT) | \ BIT(APICV_INHIBIT_REASON_HYPERV) | \ + BIT(APICV_INHIBIT_REASON_HYPERV_VP_ASSIST) | \ BIT(APICV_INHIBIT_REASON_BLOCKIRQ) | \ BIT(APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED) | \ BIT(APICV_INHIBIT_REASON_APIC_ID_MODIFIED) | \ -- 2.45.2
