summaryrefslogtreecommitdiffstats
path: root/arch
diff options
context:
space:
mode:
authorPaolo Bonzini <pbonzini@redhat.com>2024-06-03 19:09:55 +0200
committerPaolo Bonzini <pbonzini@redhat.com>2024-06-03 19:18:08 +0200
commitb3233c737ec5bf8b35130cdb6b3fe49b26a2be99 (patch)
tree03e0f256efd03158095f9f010f94ffd8b5c84061 /arch
parentLinux 6.10-rc2 (diff)
parentKVM: x86: Drop support for hand tuning APIC timer advancement from userspace (diff)
downloadlinux-b3233c737ec5bf8b35130cdb6b3fe49b26a2be99.tar.xz
linux-b3233c737ec5bf8b35130cdb6b3fe49b26a2be99.zip
Merge branch 'kvm-fixes-6.10-1' into HEAD
* Fixes and debugging help for the #VE sanity check. Also disable it by default, even for CONFIG_DEBUG_KERNEL, because it was found to trigger spuriously (most likely a processor erratum as the exact symptoms vary by generation). * Avoid WARN() when two NMIs arrive simultaneously during an NMI-disabled situation (GIF=0 or interrupt shadow) when the processor supports virtual NMI. While generally KVM will not request an NMI window when virtual NMIs are supported, in this case it *does* have to single-step over the interrupt shadow or enable the STGI intercept, in order to deliver the latched second NMI. * Drop support for hand tuning APIC timer advancement from userspace. Since we have adaptive tuning, and it has proved to work well, drop the module parameter for manual configuration and with it a few stupid bugs that it had.
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/include/asm/kvm_host.h1
-rw-r--r--arch/x86/include/asm/vmxfeatures.h2
-rw-r--r--arch/x86/kvm/Kconfig11
-rw-r--r--arch/x86/kvm/lapic.c39
-rw-r--r--arch/x86/kvm/lapic.h2
-rw-r--r--arch/x86/kvm/mmu/mmu.c43
-rw-r--r--arch/x86/kvm/mmu/spte.h9
-rw-r--r--arch/x86/kvm/mmu/tdp_iter.h2
-rw-r--r--arch/x86/kvm/mmu/tdp_mmu.c2
-rw-r--r--arch/x86/kvm/svm/sev.c19
-rw-r--r--arch/x86/kvm/svm/svm.c69
-rw-r--r--arch/x86/kvm/svm/svm.h4
-rw-r--r--arch/x86/kvm/vmx/nested.c5
-rw-r--r--arch/x86/kvm/vmx/vmx.c11
-rw-r--r--arch/x86/kvm/x86.c11
15 files changed, 161 insertions, 69 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ece45b3f6f20..f8ca74e7678f 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2154,6 +2154,7 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu);
int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
void *insn, int insn_len);
+void kvm_mmu_print_sptes(struct kvm_vcpu *vcpu, gpa_t gpa, const char *msg);
void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva);
void kvm_mmu_invalidate_addr(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
u64 addr, unsigned long roots);
diff --git a/arch/x86/include/asm/vmxfeatures.h b/arch/x86/include/asm/vmxfeatures.h
index 266daf5b5b84..695f36664889 100644
--- a/arch/x86/include/asm/vmxfeatures.h
+++ b/arch/x86/include/asm/vmxfeatures.h
@@ -77,7 +77,7 @@
#define VMX_FEATURE_ENCLS_EXITING ( 2*32+ 15) /* "" VM-Exit on ENCLS (leaf dependent) */
#define VMX_FEATURE_RDSEED_EXITING ( 2*32+ 16) /* "" VM-Exit on RDSEED */
#define VMX_FEATURE_PAGE_MOD_LOGGING ( 2*32+ 17) /* "pml" Log dirty pages into buffer */
-#define VMX_FEATURE_EPT_VIOLATION_VE ( 2*32+ 18) /* "" Conditionally reflect EPT violations as #VE exceptions */
+#define VMX_FEATURE_EPT_VIOLATION_VE ( 2*32+ 18) /* Conditionally reflect EPT violations as #VE exceptions */
#define VMX_FEATURE_PT_CONCEAL_VMX ( 2*32+ 19) /* "" Suppress VMX indicators in Processor Trace */
#define VMX_FEATURE_XSAVES ( 2*32+ 20) /* "" Enable XSAVES and XRSTORS in guest */
#define VMX_FEATURE_MODE_BASED_EPT_EXEC ( 2*32+ 22) /* "ept_mode_based_exec" Enable separate EPT EXEC bits for supervisor vs. user */
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index d64fb2b3eb69..fec95a770270 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -44,6 +44,7 @@ config KVM
select KVM_VFIO
select HAVE_KVM_PM_NOTIFIER if PM
select KVM_GENERIC_HARDWARE_ENABLING
+ select KVM_WERROR if WERROR
help
Support hosting fully virtualized guest machines using hardware
virtualization extensions. You will need a fairly recent
@@ -66,7 +67,7 @@ config KVM_WERROR
# FRAME_WARN, i.e. KVM_WERROR=y with KASAN=y requires special tuning.
# Building KVM with -Werror and KASAN is still doable via enabling
# the kernel-wide WERROR=y.
- depends on KVM && EXPERT && !KASAN
+ depends on KVM && ((EXPERT && !KASAN) || WERROR)
help
Add -Werror to the build flags for KVM.
@@ -97,15 +98,17 @@ config KVM_INTEL
config KVM_INTEL_PROVE_VE
bool "Check that guests do not receive #VE exceptions"
- default KVM_PROVE_MMU || DEBUG_KERNEL
- depends on KVM_INTEL
+ depends on KVM_INTEL && EXPERT
help
-
Checks that KVM's page table management code will not incorrectly
let guests receive a virtualization exception. Virtualization
exceptions will be trapped by the hypervisor rather than injected
in the guest.
+ Note: some CPUs appear to generate spurious EPT Violations #VEs
+ that trigger KVM's WARN, in particular with eptad=0 and/or nested
+ virtualization.
+
If unsure, say N.
config X86_SGX_KVM
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index ebf41023be38..acd7d48100a1 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -59,7 +59,17 @@
#define MAX_APIC_VECTOR 256
#define APIC_VECTORS_PER_REG 32
-static bool lapic_timer_advance_dynamic __read_mostly;
+/*
+ * Enable local APIC timer advancement (tscdeadline mode only) with adaptive
+ * tuning. When enabled, KVM programs the host timer event to fire early, i.e.
+ * before the deadline expires, to account for the delay between taking the
+ * VM-Exit (to inject the guest event) and the subsequent VM-Enter to resume
+ * the guest, i.e. so that the interrupt arrives in the guest with minimal
+ * latency relative to the deadline programmed by the guest.
+ */
+static bool lapic_timer_advance __read_mostly = true;
+module_param(lapic_timer_advance, bool, 0444);
+
#define LAPIC_TIMER_ADVANCE_ADJUST_MIN 100 /* clock cycles */
#define LAPIC_TIMER_ADVANCE_ADJUST_MAX 10000 /* clock cycles */
#define LAPIC_TIMER_ADVANCE_NS_INIT 1000
@@ -1854,16 +1864,14 @@ static void __kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
trace_kvm_wait_lapic_expire(vcpu->vcpu_id, guest_tsc - tsc_deadline);
- if (lapic_timer_advance_dynamic) {
- adjust_lapic_timer_advance(vcpu, guest_tsc - tsc_deadline);
- /*
- * If the timer fired early, reread the TSC to account for the
- * overhead of the above adjustment to avoid waiting longer
- * than is necessary.
- */
- if (guest_tsc < tsc_deadline)
- guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
- }
+ adjust_lapic_timer_advance(vcpu, guest_tsc - tsc_deadline);
+
+ /*
+ * If the timer fired early, reread the TSC to account for the overhead
+ * of the above adjustment to avoid waiting longer than is necessary.
+ */
+ if (guest_tsc < tsc_deadline)
+ guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
if (guest_tsc < tsc_deadline)
__wait_lapic_expire(vcpu, tsc_deadline - guest_tsc);
@@ -2812,7 +2820,7 @@ static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
return HRTIMER_NORESTART;
}
-int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns)
+int kvm_create_lapic(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic;
@@ -2845,13 +2853,8 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns)
hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
HRTIMER_MODE_ABS_HARD);
apic->lapic_timer.timer.function = apic_timer_fn;
- if (timer_advance_ns == -1) {
+ if (lapic_timer_advance)
apic->lapic_timer.timer_advance_ns = LAPIC_TIMER_ADVANCE_NS_INIT;
- lapic_timer_advance_dynamic = true;
- } else {
- apic->lapic_timer.timer_advance_ns = timer_advance_ns;
- lapic_timer_advance_dynamic = false;
- }
/*
* Stuff the APIC ENABLE bit in lieu of temporarily incrementing
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 0a0ea4b5dd8c..a69e706b9080 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -85,7 +85,7 @@ struct kvm_lapic {
struct dest_map;
-int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns);
+int kvm_create_lapic(struct kvm_vcpu *vcpu);
void kvm_free_lapic(struct kvm_vcpu *vcpu);
int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 662f62dfb2aa..b7b4426a7221 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -336,16 +336,19 @@ static int is_cpuid_PSE36(void)
#ifdef CONFIG_X86_64
static void __set_spte(u64 *sptep, u64 spte)
{
+ KVM_MMU_WARN_ON(is_ept_ve_possible(spte));
WRITE_ONCE(*sptep, spte);
}
static void __update_clear_spte_fast(u64 *sptep, u64 spte)
{
+ KVM_MMU_WARN_ON(is_ept_ve_possible(spte));
WRITE_ONCE(*sptep, spte);
}
static u64 __update_clear_spte_slow(u64 *sptep, u64 spte)
{
+ KVM_MMU_WARN_ON(is_ept_ve_possible(spte));
return xchg(sptep, spte);
}
@@ -4101,23 +4104,31 @@ static int get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level
return leaf;
}
-/* return true if reserved bit(s) are detected on a valid, non-MMIO SPTE. */
-static bool get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep)
+static int get_sptes_lockless(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes,
+ int *root_level)
{
- u64 sptes[PT64_ROOT_MAX_LEVEL + 1];
- struct rsvd_bits_validate *rsvd_check;
- int root, leaf, level;
- bool reserved = false;
+ int leaf;
walk_shadow_page_lockless_begin(vcpu);
if (is_tdp_mmu_active(vcpu))
- leaf = kvm_tdp_mmu_get_walk(vcpu, addr, sptes, &root);
+ leaf = kvm_tdp_mmu_get_walk(vcpu, addr, sptes, root_level);
else
- leaf = get_walk(vcpu, addr, sptes, &root);
+ leaf = get_walk(vcpu, addr, sptes, root_level);
walk_shadow_page_lockless_end(vcpu);
+ return leaf;
+}
+/* return true if reserved bit(s) are detected on a valid, non-MMIO SPTE. */
+static bool get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep)
+{
+ u64 sptes[PT64_ROOT_MAX_LEVEL + 1];
+ struct rsvd_bits_validate *rsvd_check;
+ int root, leaf, level;
+ bool reserved = false;
+
+ leaf = get_sptes_lockless(vcpu, addr, sptes, &root);
if (unlikely(leaf < 0)) {
*sptep = 0ull;
return reserved;
@@ -5921,6 +5932,22 @@ emulate:
}
EXPORT_SYMBOL_GPL(kvm_mmu_page_fault);
+void kvm_mmu_print_sptes(struct kvm_vcpu *vcpu, gpa_t gpa, const char *msg)
+{
+ u64 sptes[PT64_ROOT_MAX_LEVEL + 1];
+ int root_level, leaf, level;
+
+ leaf = get_sptes_lockless(vcpu, gpa, sptes, &root_level);
+ if (unlikely(leaf < 0))
+ return;
+
+ pr_err("%s %llx", msg, gpa);
+ for (level = root_level; level >= leaf; level--)
+ pr_cont(", spte[%d] = 0x%llx", level, sptes[level]);
+ pr_cont("\n");
+}
+EXPORT_SYMBOL_GPL(kvm_mmu_print_sptes);
+
static void __kvm_mmu_invalidate_addr(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
u64 addr, hpa_t root_hpa)
{
diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index 5dd5405fa07a..52fa004a1fbc 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -3,6 +3,8 @@
#ifndef KVM_X86_MMU_SPTE_H
#define KVM_X86_MMU_SPTE_H
+#include <asm/vmx.h>
+
#include "mmu.h"
#include "mmu_internal.h"
@@ -276,6 +278,13 @@ static inline bool is_shadow_present_pte(u64 pte)
return !!(pte & SPTE_MMU_PRESENT_MASK);
}
+static inline bool is_ept_ve_possible(u64 spte)
+{
+ return (shadow_present_mask & VMX_EPT_SUPPRESS_VE_BIT) &&
+ !(spte & VMX_EPT_SUPPRESS_VE_BIT) &&
+ (spte & VMX_EPT_RWX_MASK) != VMX_EPT_MISCONFIG_WX_VALUE;
+}
+
/*
* Returns true if A/D bits are supported in hardware and are enabled by KVM.
* When enabled, KVM uses A/D bits for all non-nested MMUs. Because L1 can
diff --git a/arch/x86/kvm/mmu/tdp_iter.h b/arch/x86/kvm/mmu/tdp_iter.h
index fae559559a80..2880fd392e0c 100644
--- a/arch/x86/kvm/mmu/tdp_iter.h
+++ b/arch/x86/kvm/mmu/tdp_iter.h
@@ -21,11 +21,13 @@ static inline u64 kvm_tdp_mmu_read_spte(tdp_ptep_t sptep)
static inline u64 kvm_tdp_mmu_write_spte_atomic(tdp_ptep_t sptep, u64 new_spte)
{
+ KVM_MMU_WARN_ON(is_ept_ve_possible(new_spte));
return xchg(rcu_dereference(sptep), new_spte);
}
static inline void __kvm_tdp_mmu_write_spte(tdp_ptep_t sptep, u64 new_spte)
{
+ KVM_MMU_WARN_ON(is_ept_ve_possible(new_spte));
WRITE_ONCE(*rcu_dereference(sptep), new_spte);
}
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 1259dd63defc..36539c1b36cd 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -626,7 +626,7 @@ static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm,
* SPTEs.
*/
handle_changed_spte(kvm, iter->as_id, iter->gfn, iter->old_spte,
- 0, iter->level, true);
+ SHADOW_NONPRESENT_VALUE, iter->level, true);
return 0;
}
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 0623cfaa7bb0..95095a233a45 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -779,6 +779,14 @@ static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu,
*/
fpstate_set_confidential(&vcpu->arch.guest_fpu);
vcpu->arch.guest_state_protected = true;
+
+ /*
+ * SEV-ES guest mandates LBR Virtualization to be _always_ ON. Enable it
+ * only after setting guest_state_protected because KVM_SET_MSRS allows
+ * dynamic toggling of LBRV (for performance reason) on write access to
+ * MSR_IA32_DEBUGCTLMSR when guest_state_protected is not set.
+ */
+ svm_enable_lbrv(vcpu);
return 0;
}
@@ -2406,6 +2414,12 @@ void __init sev_hardware_setup(void)
if (!boot_cpu_has(X86_FEATURE_SEV_ES))
goto out;
+ if (!lbrv) {
+ WARN_ONCE(!boot_cpu_has(X86_FEATURE_LBRV),
+ "LBRV must be present for SEV-ES support");
+ goto out;
+ }
+
/* Has the system been allocated ASIDs for SEV-ES? */
if (min_sev_asid == 1)
goto out;
@@ -3216,7 +3230,6 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm)
struct kvm_vcpu *vcpu = &svm->vcpu;
svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE;
- svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK;
/*
* An SEV-ES guest requires a VMSA area that is a separate from the
@@ -3268,10 +3281,6 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm)
/* Clear intercepts on selected MSRs */
set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1);
set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1);
- set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1);
- set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1);
- set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1);
- set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1);
}
void sev_init_vmcb(struct vcpu_svm *svm)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index c8dc25886c16..296c524988f9 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -99,6 +99,7 @@ static const struct svm_direct_access_msrs {
{ .index = MSR_IA32_SPEC_CTRL, .always = false },
{ .index = MSR_IA32_PRED_CMD, .always = false },
{ .index = MSR_IA32_FLUSH_CMD, .always = false },
+ { .index = MSR_IA32_DEBUGCTLMSR, .always = false },
{ .index = MSR_IA32_LASTBRANCHFROMIP, .always = false },
{ .index = MSR_IA32_LASTBRANCHTOIP, .always = false },
{ .index = MSR_IA32_LASTINTFROMIP, .always = false },
@@ -215,7 +216,7 @@ int vgif = true;
module_param(vgif, int, 0444);
/* enable/disable LBR virtualization */
-static int lbrv = true;
+int lbrv = true;
module_param(lbrv, int, 0444);
static int tsc_scaling = true;
@@ -990,7 +991,7 @@ void svm_copy_lbrs(struct vmcb *to_vmcb, struct vmcb *from_vmcb)
vmcb_mark_dirty(to_vmcb, VMCB_LBR);
}
-static void svm_enable_lbrv(struct kvm_vcpu *vcpu)
+void svm_enable_lbrv(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
@@ -1000,6 +1001,9 @@ static void svm_enable_lbrv(struct kvm_vcpu *vcpu)
set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1);
set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1);
+ if (sev_es_guest(vcpu->kvm))
+ set_msr_interception(vcpu, svm->msrpm, MSR_IA32_DEBUGCTLMSR, 1, 1);
+
/* Move the LBR msrs to the vmcb02 so that the guest can see them. */
if (is_guest_mode(vcpu))
svm_copy_lbrs(svm->vmcb, svm->vmcb01.ptr);
@@ -1009,6 +1013,8 @@ static void svm_disable_lbrv(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
+ KVM_BUG_ON(sev_es_guest(vcpu->kvm), vcpu->kvm);
+
svm->vmcb->control.virt_ext &= ~LBR_CTL_ENABLE_MASK;
set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 0, 0);
set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 0, 0);
@@ -2822,10 +2828,24 @@ static int svm_get_msr_feature(struct kvm_msr_entry *msr)
return 0;
}
+static bool
+sev_es_prevent_msr_access(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+{
+ return sev_es_guest(vcpu->kvm) &&
+ vcpu->arch.guest_state_protected &&
+ svm_msrpm_offset(msr_info->index) != MSR_INVALID &&
+ !msr_write_intercepted(vcpu, msr_info->index);
+}
+
static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
struct vcpu_svm *svm = to_svm(vcpu);
+ if (sev_es_prevent_msr_access(vcpu, msr_info)) {
+ msr_info->data = 0;
+ return -EINVAL;
+ }
+
switch (msr_info->index) {
case MSR_AMD64_TSC_RATIO:
if (!msr_info->host_initiated &&
@@ -2976,6 +2996,10 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
u32 ecx = msr->index;
u64 data = msr->data;
+
+ if (sev_es_prevent_msr_access(vcpu, msr))
+ return -EINVAL;
+
switch (ecx) {
case MSR_AMD64_TSC_RATIO:
@@ -3846,16 +3870,27 @@ static void svm_enable_nmi_window(struct kvm_vcpu *vcpu)
struct vcpu_svm *svm = to_svm(vcpu);
/*
- * KVM should never request an NMI window when vNMI is enabled, as KVM
- * allows at most one to-be-injected NMI and one pending NMI, i.e. if
- * two NMIs arrive simultaneously, KVM will inject one and set
- * V_NMI_PENDING for the other. WARN, but continue with the standard
- * single-step approach to try and salvage the pending NMI.
+ * If NMIs are outright masked, i.e. the vCPU is already handling an
+ * NMI, and KVM has not yet intercepted an IRET, then there is nothing
+ * more to do at this time as KVM has already enabled IRET intercepts.
+ * If KVM has already intercepted IRET, then single-step over the IRET,
+ * as NMIs aren't architecturally unmasked until the IRET completes.
+ *
+ * If vNMI is enabled, KVM should never request an NMI window if NMIs
+ * are masked, as KVM allows at most one to-be-injected NMI and one
+ * pending NMI. If two NMIs arrive simultaneously, KVM will inject one
+ * NMI and set V_NMI_PENDING for the other, but if and only if NMIs are
+ * unmasked. KVM _will_ request an NMI window in some situations, e.g.
+ * if the vCPU is in an STI shadow or if GIF=0, KVM can't immediately
+ * inject the NMI. In those situations, KVM needs to single-step over
+ * the STI shadow or intercept STGI.
*/
- WARN_ON_ONCE(is_vnmi_enabled(svm));
+ if (svm_get_nmi_mask(vcpu)) {
+ WARN_ON_ONCE(is_vnmi_enabled(svm));
- if (svm_get_nmi_mask(vcpu) && !svm->awaiting_iret_completion)
- return; /* IRET will cause a vm exit */
+ if (!svm->awaiting_iret_completion)
+ return; /* IRET will cause a vm exit */
+ }
/*
* SEV-ES guests are responsible for signaling when a vCPU is ready to
@@ -5265,6 +5300,12 @@ static __init int svm_hardware_setup(void)
nrips = nrips && boot_cpu_has(X86_FEATURE_NRIPS);
+ if (lbrv) {
+ if (!boot_cpu_has(X86_FEATURE_LBRV))
+ lbrv = false;
+ else
+ pr_info("LBR virtualization supported\n");
+ }
/*
* Note, SEV setup consumes npt_enabled and enable_mmio_caching (which
* may be modified by svm_adjust_mmio_mask()), as well as nrips.
@@ -5318,14 +5359,6 @@ static __init int svm_hardware_setup(void)
svm_x86_ops.set_vnmi_pending = NULL;
}
-
- if (lbrv) {
- if (!boot_cpu_has(X86_FEATURE_LBRV))
- lbrv = false;
- else
- pr_info("LBR virtualization supported\n");
- }
-
if (!enable_pmu)
pr_info("PMU virtualization is disabled\n");
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index be57213cd295..0f1472690b59 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -30,7 +30,7 @@
#define IOPM_SIZE PAGE_SIZE * 3
#define MSRPM_SIZE PAGE_SIZE * 2
-#define MAX_DIRECT_ACCESS_MSRS 47
+#define MAX_DIRECT_ACCESS_MSRS 48
#define MSRPM_OFFSETS 32
extern u32 msrpm_offsets[MSRPM_OFFSETS] __read_mostly;
extern bool npt_enabled;
@@ -39,6 +39,7 @@ extern int vgif;
extern bool intercept_smi;
extern bool x2avic_enabled;
extern bool vnmi;
+extern int lbrv;
/*
* Clean bits in VMCB.
@@ -552,6 +553,7 @@ u32 *svm_vcpu_alloc_msrpm(void);
void svm_vcpu_init_msrpm(struct kvm_vcpu *vcpu, u32 *msrpm);
void svm_vcpu_free_msrpm(u32 *msrpm);
void svm_copy_lbrs(struct vmcb *to_vmcb, struct vmcb *from_vmcb);
+void svm_enable_lbrv(struct kvm_vcpu *vcpu);
void svm_update_lbrv(struct kvm_vcpu *vcpu);
int svm_set_efer(struct kvm_vcpu *vcpu, u64 efer);
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index d5b832126e34..643935a0f70a 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2242,6 +2242,9 @@ static void prepare_vmcs02_constant_state(struct vcpu_vmx *vmx)
vmcs_write64(EPT_POINTER,
construct_eptp(&vmx->vcpu, 0, PT64_ROOT_4LEVEL));
+ if (vmx->ve_info)
+ vmcs_write64(VE_INFORMATION_ADDRESS, __pa(vmx->ve_info));
+
/* All VMFUNCs are currently emulated through L0 vmexits. */
if (cpu_has_vmx_vmfunc())
vmcs_write64(VM_FUNCTION_CONTROL, 0);
@@ -6230,6 +6233,8 @@ static bool nested_vmx_l0_wants_exit(struct kvm_vcpu *vcpu,
else if (is_alignment_check(intr_info) &&
!vmx_guest_inject_ac(vcpu))
return true;
+ else if (is_ve_fault(intr_info))
+ return true;
return false;
case EXIT_REASON_EXTERNAL_INTERRUPT:
return true;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 6051fad5945f..b3c83c06f826 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5218,8 +5218,15 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu)
if (is_invalid_opcode(intr_info))
return handle_ud(vcpu);
- if (KVM_BUG_ON(is_ve_fault(intr_info), vcpu->kvm))
- return -EIO;
+ if (WARN_ON_ONCE(is_ve_fault(intr_info))) {
+ struct vmx_ve_information *ve_info = vmx->ve_info;
+
+ WARN_ONCE(ve_info->exit_reason != EXIT_REASON_EPT_VIOLATION,
+ "Unexpected #VE on VM-Exit reason 0x%x", ve_info->exit_reason);
+ dump_vmcs(vcpu);
+ kvm_mmu_print_sptes(vcpu, ve_info->guest_physical_address, "#VE");
+ return 1;
+ }
error_code = 0;
if (intr_info & INTR_INFO_DELIVER_CODE_MASK)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 082ac6d95a3a..8c9e4281d978 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -164,15 +164,6 @@ module_param(kvmclock_periodic_sync, bool, 0444);
static u32 __read_mostly tsc_tolerance_ppm = 250;
module_param(tsc_tolerance_ppm, uint, 0644);
-/*
- * lapic timer advance (tscdeadline mode only) in nanoseconds. '-1' enables
- * adaptive tuning starting from default advancement of 1000ns. '0' disables
- * advancement entirely. Any other value is used as-is and disables adaptive
- * tuning, i.e. allows privileged userspace to set an exact advancement time.
- */
-static int __read_mostly lapic_timer_advance_ns = -1;
-module_param(lapic_timer_advance_ns, int, 0644);
-
static bool __read_mostly vector_hashing = true;
module_param(vector_hashing, bool, 0444);
@@ -12169,7 +12160,7 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
if (r < 0)
return r;
- r = kvm_create_lapic(vcpu, lapic_timer_advance_ns);
+ r = kvm_create_lapic(vcpu);
if (r < 0)
goto fail_mmu_destroy;