[PATCH] KVM: arm64: vgic: Check the interrupt is still ours before migrating it

[Marc Zyngier]

On Fri, 05 Jun 2026 05:59:15 +0900, Hyunwoo Kim wrote:
> vgic_prune_ap_list() drops both ap_list_lock and irq_lock while migrating
> an interrupt to another vCPU. After reacquiring the locks it only checks
> that the affinity is unchanged (target_vcpu == vgic_target_oracle(irq))
> before moving the interrupt, which assumes that an interrupt whose affinity
> is preserved is still queued on this vCPU's ap_list.
> 
> That assumption no longer holds if the interrupt is taken off the ap_list
> while the locks are dropped. vgic_flush_pending_lpis() removes the
> interrupt from the list and sets irq->vcpu to NULL, but leaves
> enabled/pending/target_vcpu untouched. As the interrupt is still enabled
> and pending, vgic_target_oracle() returns the same target_vcpu, so the
> affinity check passes and list_del() is run a second time on an entry that
> has already been removed.
> 
> [...]

Applied to fixes, thanks!

[1/1] KVM: arm64: vgic: Check the interrupt is still ours before migrating it
      commit: 0074b82cdfcb5fd13710a0ac308ade68ac6f6fbe

Cheers,

	M.
-- 
Without deviation from the norm, progress is not possible.