On Thu, Dec 22, 2022 at 4:47 PM Peter Xu <peterx@xxxxxxxxxx> wrote: > > On Fri, Oct 21, 2022 at 04:36:51PM +0000, James Houghton wrote: > > @@ -1990,6 +1990,17 @@ static int userfaultfd_api(struct userfaultfd_ctx *ctx, > > ~(UFFD_FEATURE_MINOR_HUGETLBFS | UFFD_FEATURE_MINOR_SHMEM); > > #ifndef CONFIG_HUGETLB_HIGH_GRANULARITY_MAPPING > > uffdio_api.features &= ~UFFD_FEATURE_MINOR_HUGETLBFS_HGM; > > +#else > > + > > + ret = -EINVAL; > > + if ((uffdio_api.features & UFFD_FEATURE_MINOR_HUGETLBFS_HGM) && > > + !(uffdio_api.features & UFFD_FEATURE_EXACT_ADDRESS)) > > This check needs to be done upon "features" or "ctx_features", rather than > "uffdio_api.features". The latter is the one we'll report to the user only. Ack, thanks Peter. I'm going to drop this patch given the API change (switching to MADV_SPLIT). - James
