From: Sean Christopherson <seanjc@google.com>
To: Vitaly Kuznetsov <vkuznets@redhat.com>,
Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Stefan Teodorescu <fane@google.com>
Subject: [PATCH 2/2] KVM: x86: Convert all runtime WARNs to ONCE variants
Date: Thu, 22 Oct 2026 14:55:41 -0700 [thread overview]
Message-ID: <20261022215541.631694-3-seanjc@google.com> (raw)
In-Reply-To: <20261022215541.631694-1-seanjc@google.com>
Bulk convert all non-ONCE WARN_ON() and WARN() calls that are reachable at
runtime to have ONCE protection, as WARNing multiple times on the same
issue rarely adds value, and if KVM is flawed/buggy, unprotected WARNs can
be leveraged by a misbehaving guest to effectively DoS the host. In the
Age of AI, such flaws/bugs are depressingly easy to find.
Reported-by: Stefan Teodorescu <fane@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/hyperv.c | 2 +-
arch/x86/kvm/i8254.c | 2 +-
arch/x86/kvm/irq.c | 4 ++--
arch/x86/kvm/lapic.c | 8 ++++----
arch/x86/kvm/mmu/tdp_mmu.c | 2 +-
arch/x86/kvm/msrs.c | 2 +-
arch/x86/kvm/svm/avic.c | 2 +-
arch/x86/kvm/svm/nested.c | 12 ++++++------
arch/x86/kvm/svm/sev.c | 2 +-
arch/x86/kvm/svm/svm.c | 12 ++++++------
arch/x86/kvm/vmx/nested.c | 12 ++++++------
arch/x86/kvm/vmx/posted_intr.c | 2 +-
arch/x86/kvm/vmx/vmx.c | 8 ++++----
arch/x86/kvm/x86.c | 18 +++++++++---------
arch/x86/kvm/x86.h | 2 +-
15 files changed, 45 insertions(+), 45 deletions(-)
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 5d2e3617c952..d9e3d49a6cc5 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1977,7 +1977,7 @@ static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu, u64 *entries, int count,
* space, just put 'flush all' entry there.
*/
if (count && entries && count < kfifo_avail(&tlb_flush_fifo->entries)) {
- WARN_ON(kfifo_in(&tlb_flush_fifo->entries, entries, count) != count);
+ WARN_ON_ONCE(kfifo_in(&tlb_flush_fifo->entries, entries, count) != count);
goto out_unlock;
}
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 1982b0077ddd..7ad8c11a1809 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -409,7 +409,7 @@ static void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
if (hpet_legacy_start) {
/* save existing mode for later reenablement */
- WARN_ON(channel != 0);
+ WARN_ON_ONCE(channel != 0);
saved_mode = pit->pit_state.channels[0].mode;
pit->pit_state.channels[0].mode = 0xff; /* disable timer */
pit_load_count(pit, channel, val);
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index 871977288272..7f8b092b4479 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -128,7 +128,7 @@ EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_cpu_has_interrupt);
int kvm_cpu_get_extint(struct kvm_vcpu *v)
{
if (!kvm_cpu_has_extint(v)) {
- WARN_ON(!lapic_in_kernel(v));
+ WARN_ON_ONCE(!lapic_in_kernel(v));
return -1;
}
@@ -513,7 +513,7 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
struct kvm *kvm = irqfd->kvm;
int ret;
- WARN_ON(irqfd->producer != prod);
+ WARN_ON_ONCE(irqfd->producer != prod);
/*
* If the producer of an IRQ that is currently being posted to a vCPU
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 61bf09badb5a..08b96b124b07 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2062,7 +2062,7 @@ static void apic_timer_expired(struct kvm_lapic *apic, bool from_timer_fn)
ktimer->expired_tscdeadline = ktimer->tscdeadline;
if (!from_timer_fn && apic->apicv_active && vcpu->wants_to_run) {
- WARN_ON(kvm_get_running_vcpu() != vcpu);
+ WARN_ON_ONCE(kvm_get_running_vcpu() != vcpu);
kvm_apic_inject_pending_timer_irqs(apic);
return;
}
@@ -2272,7 +2272,7 @@ static void cancel_hv_timer(struct kvm_lapic *apic)
{
lockdep_assert_preemption_disabled();
- WARN_ON(!apic->lapic_timer.hv_timer_in_use);
+ WARN_ON_ONCE(!apic->lapic_timer.hv_timer_in_use);
kvm_x86_call(cancel_hv_timer)(apic->vcpu);
apic->lapic_timer.hv_timer_in_use = false;
}
@@ -2359,7 +2359,7 @@ void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu)
/* If the preempt notifier has already run, it also called apic_timer_expired */
if (!apic->lapic_timer.hv_timer_in_use)
goto out;
- WARN_ON(kvm_vcpu_is_blocking(vcpu));
+ WARN_ON_ONCE(kvm_vcpu_is_blocking(vcpu));
apic_timer_expired(apic, false);
cancel_hv_timer(apic);
@@ -2392,7 +2392,7 @@ void kvm_lapic_restart_hv_timer(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
- WARN_ON(!apic->lapic_timer.hv_timer_in_use);
+ WARN_ON_ONCE(!apic->lapic_timer.hv_timer_in_use);
restart_apic_timer(apic);
}
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 44dad106fad1..945efc1cfaea 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -1368,7 +1368,7 @@ static bool __kvm_tdp_mmu_age_gfn_range(struct kvm *kvm,
* this helper must NOT be used to unmap GFNs, as it processes only
* valid roots!
*/
- WARN_ON(types & ~KVM_VALID_ROOTS);
+ WARN_ON_ONCE(types & ~KVM_VALID_ROOTS);
guard(rcu)();
for_each_tdp_mmu_root_rcu(kvm, root, range->slot->as_id, types) {
diff --git a/arch/x86/kvm/msrs.c b/arch/x86/kvm/msrs.c
index e91650af44c2..b8ab784704fa 100644
--- a/arch/x86/kvm/msrs.c
+++ b/arch/x86/kvm/msrs.c
@@ -643,7 +643,7 @@ static int set_efer(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
r = kvm_x86_call(set_efer)(vcpu, efer);
if (r) {
- WARN_ON(r > 0);
+ WARN_ON_ONCE(r > 0);
return r;
}
diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 3b037e385523..0042039e15e3 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -1042,7 +1042,7 @@ static void __avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu,
lockdep_assert_preemption_disabled();
- if (WARN_ON(h_physical_id & ~AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK))
+ if (WARN_ON_ONCE(h_physical_id & ~AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK))
return;
if (WARN_ON_ONCE(vcpu->vcpu_id * sizeof(entry) >=
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index af0ef678433d..ab66f07337b5 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -100,7 +100,7 @@ static void nested_svm_init_mmu_context(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
- WARN_ON(mmu_is_nested(vcpu));
+ WARN_ON_ONCE(mmu_is_nested(vcpu));
vcpu->arch.mmu = &vcpu->arch.guest_mmu;
@@ -260,7 +260,7 @@ int __init nested_svm_init_msrpm_merge_offsets(void)
int bit_nr = svm_msrpm_bit_nr(merge_msrs[i]);
u32 offset;
- if (WARN_ON(bit_nr < 0))
+ if (WARN_ON_ONCE(bit_nr < 0))
return -EIO;
/*
@@ -277,7 +277,7 @@ int __init nested_svm_init_msrpm_merge_offsets(void)
if (j < nested_svm_nr_msrpm_merge_offsets)
continue;
- if (WARN_ON(j >= ARRAY_SIZE(nested_svm_msrpm_merge_offsets)))
+ if (WARN_ON_ONCE(j >= ARRAY_SIZE(nested_svm_msrpm_merge_offsets)))
return -EIO;
nested_svm_msrpm_merge_offsets[j] = offset;
@@ -1065,7 +1065,7 @@ int enter_svm_guest_mode(struct kvm_vcpu *vcpu, u64 vmcb12_gpa, bool from_vmrun)
svm->nested.vmcb12_gpa = vmcb12_gpa;
- WARN_ON(svm->vmcb == svm->nested.vmcb02.ptr);
+ WARN_ON_ONCE(svm->vmcb == svm->nested.vmcb02.ptr);
nested_svm_copy_common_state(svm->vmcb01.ptr, svm->nested.vmcb02.ptr);
@@ -1716,7 +1716,7 @@ static void nested_svm_inject_exception_vmexit(struct kvm_vcpu *vcpu)
kvm_update_dr7(vcpu);
}
} else {
- WARN_ON(ex->has_payload);
+ WARN_ON_ONCE(ex->has_payload);
}
nested_svm_vmexit(svm);
@@ -2123,7 +2123,7 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
{
- if (WARN_ON(!is_guest_mode(vcpu)))
+ if (WARN_ON_ONCE(!is_guest_mode(vcpu)))
return true;
if (is_pae_paging(vcpu)) {
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 6427db390b1c..8cd0f1539829 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3007,7 +3007,7 @@ void sev_vm_destroy(struct kvm *kvm)
if (!sev_guest(kvm))
return;
- WARN_ON(!list_empty(&sev->mirror_vms));
+ WARN_ON_ONCE(!list_empty(&sev->mirror_vms));
/*
* If this is a mirror VM, remove it from the owner's list of a mirrors
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 487897ef11dd..c8e82debb7f4 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1598,7 +1598,7 @@ static void svm_set_vintr(struct vcpu_svm *svm)
/*
* The following fields are ignored when AVIC is enabled
*/
- WARN_ON(kvm_vcpu_apicv_activated(&svm->vcpu));
+ WARN_ON_ONCE(kvm_vcpu_apicv_activated(&svm->vcpu));
svm_set_intercept(svm, INTERCEPT_VINTR);
@@ -1633,8 +1633,8 @@ static void svm_clear_vintr(struct vcpu_svm *svm)
if (is_guest_mode(&svm->vcpu)) {
svm->vmcb01.ptr->control.int_ctl &= ~V_IRQ_INJECTION_BITS_MASK;
- WARN_ON((svm->vmcb->control.int_ctl & V_TPR_MASK) !=
- (svm->nested.ctl.int_ctl & V_TPR_MASK));
+ WARN_ON_ONCE((svm->vmcb->control.int_ctl & V_TPR_MASK) !=
+ (svm->nested.ctl.int_ctl & V_TPR_MASK));
svm->vmcb->control.int_ctl |= svm->nested.ctl.int_ctl &
V_IRQ_INJECTION_BITS_MASK;
@@ -2666,7 +2666,7 @@ static int cr_interception(struct kvm_vcpu *vcpu)
err = kvm_set_cr8(vcpu, val);
break;
default:
- WARN(1, "unhandled write to CR%d", cr);
+ WARN_ONCE(1, "unhandled write to CR%d", cr);
kvm_queue_exception(vcpu, UD_VECTOR);
return 1;
}
@@ -2688,7 +2688,7 @@ static int cr_interception(struct kvm_vcpu *vcpu)
val = kvm_get_cr8(vcpu);
break;
default:
- WARN(1, "unhandled read from CR%d", cr);
+ WARN_ONCE(1, "unhandled read from CR%d", cr);
kvm_queue_exception(vcpu, UD_VECTOR);
return 1;
}
@@ -2725,7 +2725,7 @@ static int cr_trap(struct kvm_vcpu *vcpu)
ret = kvm_set_cr8(vcpu, new_value);
break;
default:
- WARN(1, "unhandled CR%d write trap", cr);
+ WARN_ONCE(1, "unhandled CR%d write trap", cr);
kvm_queue_exception(vcpu, UD_VECTOR);
return 1;
}
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 9b0bfa2f854c..ec3bc441a0e6 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -515,7 +515,7 @@ static void nested_ept_new_eptp(struct kvm_vcpu *vcpu)
static void nested_ept_init_mmu_context(struct kvm_vcpu *vcpu)
{
- WARN_ON(mmu_is_nested(vcpu));
+ WARN_ON_ONCE(mmu_is_nested(vcpu));
vcpu->arch.mmu = &vcpu->arch.guest_mmu;
nested_ept_new_eptp(vcpu);
@@ -1315,7 +1315,7 @@ static void nested_vmx_transition_tlb_flush(struct kvm_vcpu *vcpu,
}
/* L2 should never have a VPID if VPID is disabled. */
- WARN_ON(!enable_vpid);
+ WARN_ON_ONCE(!enable_vpid);
/*
* VPID is enabled and in use by vmcs12. If vpid12 is changing, then
@@ -1698,7 +1698,7 @@ static void copy_shadow_to_vmcs12(struct vcpu_vmx *vmx)
unsigned long val;
int i;
- if (WARN_ON(!shadow_vmcs))
+ if (WARN_ON_ONCE(!shadow_vmcs))
return;
preempt_disable();
@@ -1733,7 +1733,7 @@ static void copy_vmcs12_to_shadow(struct vcpu_vmx *vmx)
unsigned long val;
int i, q;
- if (WARN_ON(!shadow_vmcs))
+ if (WARN_ON_ONCE(!shadow_vmcs))
return;
vmcs_load(shadow_vmcs);
@@ -4978,7 +4978,7 @@ static void nested_vmx_restore_host_state(struct kvm_vcpu *vcpu)
if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)
kvm_set_dr(vcpu, 7, DR7_FIXED_1);
else
- WARN_ON(kvm_set_dr(vcpu, 7, vmcs_readl(GUEST_DR7)));
+ WARN_ON_ONCE(kvm_set_dr(vcpu, 7, vmcs_readl(GUEST_DR7)));
}
/* Reload DEBUGCTL to ensure vmcs01 has a fresh FREEZE_IN_SMM value. */
@@ -5408,7 +5408,7 @@ static struct vmcs *alloc_shadow_vmcs(struct kvm_vcpu *vcpu)
* doesn't support virtualization of VMCS shadowing, so vmcs01 should
* always be the loaded VMCS.
*/
- if (WARN_ON(loaded_vmcs != &vmx->vmcs01 || loaded_vmcs->shadow_vmcs))
+ if (WARN_ON_ONCE(loaded_vmcs != &vmx->vmcs01 || loaded_vmcs->shadow_vmcs))
return loaded_vmcs->shadow_vmcs;
loaded_vmcs->shadow_vmcs = alloc_vmcs(true);
diff --git a/arch/x86/kvm/vmx/posted_intr.c b/arch/x86/kvm/vmx/posted_intr.c
index 2644add54b76..0f508015692b 100644
--- a/arch/x86/kvm/vmx/posted_intr.c
+++ b/arch/x86/kvm/vmx/posted_intr.c
@@ -187,7 +187,7 @@ static void pi_enable_wakeup_handler(struct kvm_vcpu *vcpu)
&per_cpu(wakeup_vcpus_on_cpu, vcpu->cpu));
raw_spin_unlock(&per_cpu(wakeup_vcpus_on_cpu_lock, vcpu->cpu));
- WARN(pi_test_sn(pi_desc), "PI descriptor SN field set before blocking");
+ WARN_ONCE(pi_test_sn(pi_desc), "PI descriptor SN field set before blocking");
old.control = READ_ONCE(pi_desc->control);
do {
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index b341af4c6057..0038626f5486 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -3089,7 +3089,7 @@ void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
loaded_vmcs->vmcs = NULL;
if (loaded_vmcs->msr_bitmap)
free_page((unsigned long)loaded_vmcs->msr_bitmap);
- WARN_ON(loaded_vmcs->shadow_vmcs != NULL);
+ WARN_ON_ONCE(loaded_vmcs->shadow_vmcs != NULL);
}
int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
@@ -4468,7 +4468,7 @@ void vmx_set_constant_host_state(struct vcpu_vmx *vmx)
unsigned long cr0, cr3, cr4;
cr0 = read_cr0();
- WARN_ON(cr0 & X86_CR0_TS);
+ WARN_ON_ONCE(cr0 & X86_CR0_TS);
vmcs_writel(HOST_CR0, cr0); /* 22.2.3 */
/*
@@ -5537,7 +5537,7 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu)
* STI and MOVSS blocking.
*/
if (is_icebp(intr_info))
- WARN_ON(!skip_emulated_instruction(vcpu));
+ WARN_ON_ONCE(!skip_emulated_instruction(vcpu));
kvm_queue_exception_p(vcpu, DB_VECTOR, dr6);
return 1;
@@ -5962,7 +5962,7 @@ static int handle_task_switch(struct kvm_vcpu *vcpu)
if (!idt_v || (type != INTR_TYPE_HARD_EXCEPTION &&
type != INTR_TYPE_EXT_INTR &&
type != INTR_TYPE_NMI_INTR))
- WARN_ON(!skip_emulated_instruction(vcpu));
+ WARN_ON_ONCE(!skip_emulated_instruction(vcpu));
/*
* TODO: What about debug traps on tss switch?
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 32563a91fba9..a9be847d3cc2 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -370,7 +370,7 @@ static int exception_type(int vector)
{
unsigned int mask;
- if (WARN_ON(vector > 31 || vector == NMI_VECTOR))
+ if (WARN_ON_ONCE(vector > 31 || vector == NMI_VECTOR))
return EXCPT_INTERRUPT;
mask = 1 << vector;
@@ -4907,7 +4907,7 @@ static int kvm_fetch_guest_virt(struct x86_emulate_ctxt *ctxt,
return X86EMUL_PROPAGATE_FAULT;
offset = addr & (PAGE_SIZE-1);
- if (WARN_ON(offset + bytes > PAGE_SIZE))
+ if (WARN_ON_ONCE(offset + bytes > PAGE_SIZE))
bytes = (unsigned)PAGE_SIZE - offset;
ret = kvm_vcpu_read_guest_page(vcpu, gpa >> PAGE_SHIFT, val,
offset, bytes);
@@ -5167,7 +5167,7 @@ static int emulator_read_write_onepage(unsigned long addr, void *val,
bytes -= handled;
val += handled;
- WARN_ON(vcpu->mmio_nr_fragments >= KVM_MAX_MMIO_FRAGMENTS);
+ WARN_ON_ONCE(vcpu->mmio_nr_fragments >= KVM_MAX_MMIO_FRAGMENTS);
frag = &vcpu->mmio_fragments[vcpu->mmio_nr_fragments++];
frag->gpa = gpa;
if (write && bytes <= 8u) {
@@ -7042,7 +7042,7 @@ static int kvm_x86_check_processor_compatibility(void)
* compatible, i.e. KVM should never perform a compatibility check on
* an offline CPU.
*/
- WARN_ON(!cpu_online(cpu));
+ WARN_ON_ONCE(!cpu_online(cpu));
if (__cr4_reserved_bits(cpu_has, c) !=
__cr4_reserved_bits(cpu_has, &boot_cpu_data))
@@ -7783,7 +7783,7 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
vcpu->arch.nmi_injected = true;
kvm_x86_call(inject_nmi)(vcpu);
can_inject = false;
- WARN_ON(kvm_x86_call(nmi_allowed)(vcpu, true) < 0);
+ WARN_ON_ONCE(kvm_x86_call(nmi_allowed)(vcpu, true) < 0);
}
if (vcpu->arch.nmi_pending)
kvm_x86_call(enable_nmi_window)(vcpu);
@@ -7800,7 +7800,7 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
if (likely(irq != -1)) {
kvm_queue_interrupt(vcpu, irq, false);
kvm_x86_call(inject_irq)(vcpu, false);
- WARN_ON(kvm_x86_call(interrupt_allowed)(vcpu, true) < 0);
+ WARN_ON_ONCE(kvm_x86_call(interrupt_allowed)(vcpu, true) < 0);
} else {
kvm_warn_on_lost_irq(vcpu);
}
@@ -8470,8 +8470,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
* KVM_DEBUGREG_WONT_EXIT again.
*/
if (unlikely(vcpu->arch.switch_db_regs & KVM_DEBUGREG_WONT_EXIT)) {
- WARN_ON(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP);
- WARN_ON(vcpu->arch.switch_db_regs & KVM_DEBUGREG_AUTO_SWITCH);
+ WARN_ON_ONCE(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP);
+ WARN_ON_ONCE(vcpu->arch.switch_db_regs & KVM_DEBUGREG_AUTO_SWITCH);
kvm_x86_call(sync_dirty_debug_regs)(vcpu);
kvm_update_dr0123(vcpu);
vcpu->arch.dr6 |= kvm_get_dr6_fixed_1(vcpu);
@@ -10038,7 +10038,7 @@ void __user * __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa,
lockdep_assert_held(&kvm->slots_lock);
- if (WARN_ON(id >= KVM_MEM_SLOTS_NUM))
+ if (WARN_ON_ONCE(id >= KVM_MEM_SLOTS_NUM))
return ERR_PTR_USR(-EINVAL);
slot = id_to_memslot(slots, id);
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index cfe96962a4e4..99ba31aa5ef5 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -348,7 +348,7 @@ static inline void adjust_tsc_offset_guest(struct kvm_vcpu *vcpu,
static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment)
{
if (vcpu->arch.l1_tsc_scaling_ratio != kvm_caps.default_tsc_scaling_ratio)
- WARN_ON(adjustment < 0);
+ WARN_ON_ONCE(adjustment < 0);
adjustment = kvm_scale_tsc((u64) adjustment,
vcpu->arch.l1_tsc_scaling_ratio);
adjust_tsc_offset_guest(vcpu, adjustment);
--
2.56.0.257.gf7497c7d27-goog
prev parent reply other threads:[~2026-10-22 21:55 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-22 21:55 [PATCH 0/2] KVM: x86: Convert all runtime WARNs to ONCE Sean Christopherson
2026-10-22 21:55 ` [PATCH 1/2] KVM: x86: Convert WARN_ON(preemptible()) to lockdep assertion Sean Christopherson
2026-10-22 21:55 ` Sean Christopherson [this message]
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