Am 10.06.24 um 18:19 schrieb Sean Christopherson:
On Mon, May 06, 2024, Yi Wang wrote:From: Yi Wang <foxywang@xxxxxxxxxxx> As we have setup empty irq routing in kvm_create_vm(), there's no need to setup dummy routing when KVM_CREATE_IRQCHIP. Signed-off-by: Yi Wang <foxywang@xxxxxxxxxxx> --- arch/s390/kvm/kvm-s390.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 5147b943a864..ba7fd39bcbf4 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2998,14 +2998,7 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) break; } case KVM_CREATE_IRQCHIP: { - struct kvm_irq_routing_entry routing; - - r = -EINVAL; - if (kvm->arch.use_irqchip) { - /* Set up dummy routing. */ - memset(&routing, 0, sizeof(routing)); - r = kvm_set_irq_routing(kvm, &routing, 0, 0); - } + r = 0;This is wrong, KVM_CREATE_IRQCHIP should fail with -EINVAL if kvm->arch.use_irqchip is false. There's also a functional change here, though I highly doubt it negatively affects userspace. Nothing in s390 prevents invoking KVM_CREATE_IRQCHIP after KVM_SET_GSI_ROUTING, so userspace could very theoretically use KVM_CREATE_IRQCHIP to reset to empty IRQ routing. Christian, if it works for you, I'll massage it to this when applying.
Oops. Yes please do so.
