2f5213b8fc
Use a magic value to signal a ucall_alloc() failure instead of simply doing GUEST_ASSERT(). GUEST_ASSERT() relies on ucall_alloc() and so a failure puts the guest into an infinite loop. Use -1 as the magic value, as a real ucall struct should never wrap. Reported-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>