From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A71AF4183B0 for ; Thu, 18 Jun 2026 18:53:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781808833; cv=none; b=bdztzcsJcANHXcW/Egvz3t4bttpEAXq5lQU/1Cu89CnjSiKqe6d4EQp2mAGpmXj2pyg4+2FXIs2IHutgt7TD38AbU++RzxqUK7pcJC78wDDalurze4xgghZWxiAveLS6spmczBKKwmQnVBMLZTZFuvpActVyMGZS9u5WyQ/9T9M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781808833; c=relaxed/simple; bh=ybD9jZBXCqB4UsvTDfL84tsRbZKiP6NIMn8m6YurzhY=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=baLweoxBh+gTl9pnIDBBKDzn0cIH2DOdh/qi1xqmpH7e8Vbz7Xvk04nBr7/37qP5k/YmrlmjUhJWRd6aIvQ/qhW2TpchvNLaXjnfeERvaH3vfwONpBWKeP18DPWSfm81ubeU308MCwxIHCUl093c1dcaOIjYanhStvAiGUXeDjo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=pY5qefCL; arc=none smtp.client-ip=209.85.210.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="pY5qefCL" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-845319bb97bso1181284b3a.0 for ; Thu, 18 Jun 2026 11:53:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1781808832; x=1782413632; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:reply-to:from:to:cc :subject:date:message-id:reply-to; bh=EV2jRPRYUe5DqipArutJ7o09RVfE+m4fdZaghLzNKlY=; b=pY5qefCLa/fen6rUBOYFAAKK8jlErvxvgUxcxhIPGdqkqx+s9NbIKM580LzMysg5xc lCRH1iMhrQ+tLMYnBTE/SziDBUSZp7wIg62KHpYfOkqOzsS7JnBW8AJcpa+f0E6dR6e8 Kh9LdfwkMwBv5RQI4Bvs/PkplUpykbRLVHD9hRGp3p0ketwXLRVz5Cv70lwM1V+d7YK0 Q8whUA6MQLs2ikZPjjY9xeWwFTCGsMkjPkqLqA8Cjb4lb+APfmC0u+FE5MkgPYbW7hPI CqZ4t5vTaXIVnp+82oxoV/X7YGTushApXpuQWdrLgVNDlJ39VJf0S+GoBAmoEnIU8fht Qy4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781808832; x=1782413632; h=cc:to:from:subject:message-id:mime-version:date:reply-to :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=EV2jRPRYUe5DqipArutJ7o09RVfE+m4fdZaghLzNKlY=; b=ZteqND4A8gAvAs9+rc3ERZueh7P7tKhgQJhXtuFqRgmqxbwAQYRu230ym0J7Nm3cPC GfFkj5WqZgjfVIPsGtaHtqcTevF9Vf1g2SNd8oQhbzvxhFUmrvb9EnMADQQymPilsgCe /FpzksNBceN43s/I3dkXP0/yaB+HwwjR/wfJRPHDVzYio2GqJTVJIJUfVkX467YK8hvU R0Ykq0STXo4Mg8smQJ0WyupLn4xe7FiBU9hZeX5g4En33DN3iGcXrqIapjv4BZF2LoUm d2IefsVaUP9vnSnKNPkKsZqTr7ivKNhhrsq2QmToozhJpcczJK9CKlOKoFt6sPC1DJB6 +SDA== X-Forwarded-Encrypted: i=1; AFNElJ/VfW5uj3GKJKsnuJAaNsfmx6brE4v3TP9zev3x6hYEcqx5ZTv5UPEP2VIwzoZ3FuFb2EsODymVCFj9VB0=@vger.kernel.org X-Gm-Message-State: AOJu0YwKg4VjzA9T60C7FZRnezGBKmZo/RZ2wxd58UV4v7haBeqgNmsS xD+xvrNOQ3My9T+vAJFqZmgqrtZdSMFSNo+oMwTUth+gS5qv41rPAGkhgV6Q5H1HVnD0YjbDZ/8 nnUW46w== X-Received: from pfbfm11.prod.google.com ([2002:a05:6a00:2f8b:b0:83e:b5cc:11c3]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:1707:b0:838:29b3:9ed1 with SMTP id d2e1a72fcca58-84550900333mr136338b3a.41.1781808831693; Thu, 18 Jun 2026 11:53:51 -0700 (PDT) Reply-To: Sean Christopherson Date: Thu, 18 Jun 2026 11:53:50 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.55.0.rc0.738.g0c8ab3ebcc-goog Message-ID: <20260618185350.2020845-1-seanjc@google.com> Subject: [PATCH] KVM: x86: Bug the VM, not the kernel, if the ISR count {under,over}flows From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Bug the VM, not the host kernel, if KVM's ISR count {under,over}flows when tracking in-flight ISRs. There is zero danger to the host if KVM messes up its IRQ tracking. Signed-off-by: Sean Christopherson --- arch/x86/kvm/lapic.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 9d2df8623f6d..e733ca6b9792 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -767,7 +767,7 @@ static inline void apic_set_isr(int vec, struct kvm_lapic *apic) kvm_x86_call(hwapic_isr_update)(apic->vcpu, vec); else { ++apic->isr_count; - BUG_ON(apic->isr_count > MAX_APIC_VECTOR); + KVM_BUG_ON(apic->isr_count > MAX_APIC_VECTOR, apic->vcpu->kvm); /* * ISR (in service register) bit is set when injecting an interrupt. * The highest vector is injected. Thus the latest bit set matches @@ -808,7 +808,7 @@ static inline void apic_clear_isr(int vec, struct kvm_lapic *apic) kvm_x86_call(hwapic_isr_update)(apic->vcpu, apic_find_highest_isr(apic)); else { --apic->isr_count; - BUG_ON(apic->isr_count < 0); + KVM_BUG_ON(apic->isr_count < 0, apic->vcpu->kvm); apic->highest_isr_cache = -1; } } base-commit: 9d4853b044beefa21c4ee3e18c40653601a64ced -- 2.55.0.rc0.738.g0c8ab3ebcc-goog