On 2023-07-26 at 08:59:53 -0700, Sean Christopherson wrote: > On Mon, Jul 24, 2023, Xu Yilun wrote: > > On 2023-07-18 at 16:44:51 -0700, Sean Christopherson wrote: > > > + if (WARN_ON_ONCE(start == end)) > > > + return -EINVAL; > > > > Also, is this check possible to be hit? Maybe remove it? > > It should be impossible to, hence the WARN. I added the check for two reasons: > (1) to help document that end is exclusive, and (2) to guard against future bugs. Understood. I'm good to it.