On 12/1/23 1:16 PM, Eric Farman wrote:
The various errors that are possible when processing a PQAP instruction (the absence of a driver hook, an error FROM that hook), all correctly set the PSW condition code to 3. But if that processing works successfully, CC0 needs to be set to convey that everything was fine. Fix the check so that the guest can examine the condition code to determine whether GPR1 has meaningful data. Fixes: e5282de93105 ("s390: ap: kvm: add PQAP interception for AQIC") Signed-off-by: Eric Farman <farman@xxxxxxxxxxxxx> --- arch/s390/kvm/priv.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index 621a17fd1a1b..f875a404a0a0 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -676,8 +676,12 @@ static int handle_pqap(struct kvm_vcpu *vcpu) if (vcpu->kvm->arch.crypto.pqap_hook) { pqap_hook = *vcpu->kvm->arch.crypto.pqap_hook; ret = pqap_hook(vcpu); - if (!ret && vcpu->run->s.regs.gprs[1] & 0x00ff0000) - kvm_s390_set_psw_cc(vcpu, 3); + if (!ret) { + if (vcpu->run->s.regs.gprs[1] & 0x00ff0000) + kvm_s390_set_psw_cc(vcpu, 3); + else + kvm_s390_set_psw_cc(vcpu, 0); + }
The cc is not set if pqap_hook returns a non-zero rc; however, this point may be moot given the only non-zero rc is -EOPNOTSUPP. I'm a bit foggy on what happens when non-zero return codes are passed up the stack.
up_read(&vcpu->kvm->arch.crypto.pqap_hook_rwsem); return ret; }