Re: [PATCH] KVM: arm64: vgic: drop WARN from vgic_get_irq
From: Oliver Upton <hidden>
Date: 2021-08-18 21:34:24
Also in:
kvmarm
Hi Ricardo, On Wed, Aug 18, 2021 at 2:32 PM Ricardo Koller [off-list ref] wrote:
quoted hunk ↗ jump to hunk
vgic_get_irq(intid) is used all over the vgic code in order to get a reference to a struct irq. It warns whenever intid is not a valid number (like when it's a reserved IRQ number). The issue is that this warning can be triggered from userspace (e.g., KVM_IRQ_LINE for intid 1020). Drop the WARN call from vgic_get_irq. Signed-off-by: Ricardo Koller <redacted> --- arch/arm64/kvm/vgic/vgic.c | 1 - 1 file changed, 1 deletion(-)diff --git a/arch/arm64/kvm/vgic/vgic.c b/arch/arm64/kvm/vgic/vgic.c index 111bff47e471..81cec508d413 100644 --- a/arch/arm64/kvm/vgic/vgic.c +++ b/arch/arm64/kvm/vgic/vgic.c@@ -106,7 +106,6 @@ struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu, if (intid >= VGIC_MIN_LPI) return vgic_get_lpi(kvm, intid); - WARN(1, "Looking up struct vgic_irq for reserved INTID");
Could we maybe downgrade the message to WARN_ONCE() (to get a stack) or pr_warn_ratelimited()? I agree it is problematic that userspace can cause this WARN to fire, but it'd be helpful for debugging too. -- Thanks, Oliver
return NULL; } -- 2.33.0.rc2.250.ged5fa647cd-goog