linux-kernel - [PATCH v2 47/59] KVM: x86: Drop superfluous "has assigned device" check in kvm_pi_update

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250523010004.3240643-48-seanjc@google.com>
Date: Thu, 22 May 2025 17:59:52 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini <pbonzini@...hat.com>, 
	Joerg Roedel <joro@...tes.org>, David Woodhouse <dwmw2@...radead.org>, 
	Lu Baolu <baolu.lu@...ux.intel.com>
Cc: kvm@...r.kernel.org, iommu@...ts.linux.dev, linux-kernel@...r.kernel.org, 
	Sairaj Kodilkar <sarunkod@....com>, Vasant Hegde <vasant.hegde@....com>, 
	Maxim Levitsky <mlevitsk@...hat.com>, Joao Martins <joao.m.martins@...cle.com>, 
	Francesco Lavra <francescolavra.fl@...il.com>, David Matlack <dmatlack@...gle.com>
Subject: [PATCH v2 47/59] KVM: x86: Drop superfluous "has assigned device"
 check in kvm_pi_update_irte()

Don't bother checking if the VM has an assigned device when updating
IRTE entries.  kvm_arch_irq_bypass_add_producer() explicitly increments
the assigned device count, kvm_arch_irq_bypass_del_producer() explicitly
decrements the count before invoking kvm_pi_update_irte(), and
kvm_irq_routing_update() only updates IRTE entries if there's an active
IRQ bypass producer.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/irq.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index 19fa3452d201..904aac4d5e08 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -517,9 +517,7 @@ static int kvm_pi_update_irte(struct kvm_kernel_irqfd *irqfd,
 	struct kvm_lapic_irq irq;
 	int r;
 
-	if (!irqchip_in_kernel(kvm) ||
-	    !kvm_arch_has_irq_bypass() ||
-	    !kvm_arch_has_assigned_device(kvm))
+	if (!irqchip_in_kernel(kvm) || !kvm_arch_has_irq_bypass())
 		return 0;
 
 	if (entry && entry->type == KVM_IRQ_ROUTING_MSI) {
-- 
2.49.0.1151.ga128411c76-goog