Paolo Bonzini <pbonzini@xxxxxxxxxx> writes: > On 07/02/20 20:53, Sean Christopherson wrote: >> >>> 2) Return -EINVAL instead. >> I agree that it _should_ be -EINVAL, but I just don't think it's worth >> the possibility of breaking (stupid) userspace that was doing something >> like: >> >> for (i = 0; i < max_cpuid_size; i++) { >> cpuid.nent = i; >> >> r = ioctl(fd, KVM_GET_SUPPORTED_CPUID, &cpuid); >> if (!r || r != -E2BIG) >> break; >> } >> > > Apart from the stupidity of the above case, why would it be EINVAL? > I suggested -EINVAL because issuing KVM_GET_SUPPORTED_CPUID with nent=0 looks more like a completely invalid input and not 'too many entries'(-E2BIG) to me (but -E2BIG is already there, let's keep it, it's not a big deal). > I can do the change to drop the initializer when applying. We're agreed with Sean on a few cosmetic changes in other patches of this series, wait for v2) -- Vitaly