On 05.05.20 10:35, Christian Borntraeger wrote: > In LPAR we will only get an intercept for FC==3 for the PQAP > instruction. Running nested under z/VM can result in other intercepts as > well as ECA_APIE is an effective bit: If one hypervisor layer has > turned this bit off, the end result will be that we will get intercepts for > all function codes. Usually the first one will be a query like PQAP(QCI). > So the WARN_ON_ONCE is not right. Let us simply remove it. > > Cc: Pierre Morel <pmorel@xxxxxxxxxxxxx> > Cc: Tony Krowiak <akrowiak@xxxxxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx > Link: https://lore.kernel.org/kvm/20200505073525.2287-1-borntraeger@xxxxxxxxxx > Reported-by: Qian Cai <cailca@xxxxxxxxxx> > Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> > Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> > Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx> > --- > arch/s390/kvm/priv.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c > index 69a824f9ef0b..893893642415 100644 > --- a/arch/s390/kvm/priv.c > +++ b/arch/s390/kvm/priv.c > @@ -626,10 +626,12 @@ static int handle_pqap(struct kvm_vcpu *vcpu) > * available for the guest are AQIC and TAPQ with the t bit set > * since we do not set IC.3 (FIII) we currently will only intercept > * the AQIC function code. > + * Note: running nested under z/VM can result in intercepts for other > + * function codes, e.g. PQAP(QCI). We do not support this and bail out. > */ > reg0 = vcpu->run->s.regs.gprs[0]; > fc = (reg0 >> 24) & 0xff; > - if (WARN_ON_ONCE(fc != 0x03)) > + if (fc != 0x03) > return -EOPNOTSUPP; > > /* PQAP instruction is allowed for guest kernel only */ > applied for kvms390/master. Qian Cai, can you verify that this fixes the issue?
