On Thu, Jul 07, 2022 at 08:42:28AM +0000, Tian, Kevin wrote: > External email: Use caution opening links or attachments > > > > From: Nicolin Chen <nicolinc@xxxxxxxxxx> > > Sent: Wednesday, July 6, 2022 2:28 PM > > > > There's only one caller that checks its return value with a WARN_ON_ONCE, > > while all other callers do not check return value at all. So simplify the > > API to return void by embedding similar WARN_ON_ONCEs. > > While this change keeps the similar effect as before it leads to different > policy for same type of errors between pin and unpin paths: I think it's because of the policy that an undo function should not fail. Meanwhile, indulging faulty inputs isn't good either. > e.g. > > vfio_unpin_pages(): > if (WARN_ON_ONCE(!user_pfn || !npage || !vfio_assert_device_open(device))) > return; > > vfio_pin_pages(): > if (!user_pfn || !phys_pfn || !npage || > !vfio_assert_device_open(device)) > return -EINVAL; > > It sounds a bit weird when reading related code... Any better way to handle this?