On 01.03.24 21:43, Eric Farman wrote:
It's possible that SIE exits for work that the host needs to perform rather than something that is intended for the guest. A Linux guest will ignore this intercept code since there is nothing for it to do, but a more robust solution would rewind the PSW back to the SIE instruction. This will transparently resume the guest once the host completes its work, without the guest needing to process what is effectively a NOP and re-issue SIE itself.
I recall that 0-intercepts are valid by the architecture. Further, I recall that there were some rather tricky corner cases where avoiding 0-intercepts would not be that easy.
Now, it's been a while ago, and maybe I misremember. SoI'm trusting people with access to documentation can review this.
-- Cheers, David / dhildenb
