Re: [PATCH] KVM: s390: vsie: fix race during shadow creation

[Christian Borntraeger <borntraeger@linux.ibm.com>]

Am 20.12.23 um 08:34 schrieb Christian Borntraeger:
> Right now it is possible to see gmap->private being zero in
> kvm_s390_vsie_gmap_notifier resulting in a crash.  This is due to the
> fact that we add gmap->private == kvm after creation:
> 
> static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
>                                 struct vsie_page *vsie_page)
> {
> [...]
>          gmap = gmap_shadow(vcpu->arch.gmap, asce, edat);
>          if (IS_ERR(gmap))
>                  return PTR_ERR(gmap);
>          gmap->private = vcpu->kvm;
> 
> Instead of tracking kvm in the shadow gmap, simply use the parent one.
> 
> Cc: David Hildenbrand <david@redhat.com>

I forgot to add
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>