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David Alan Gilbert" , "Matthew Wilcox (Oracle)" , Vlastimil Babka , Baolin Wang , Miaohe Lin , Yang Shi , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 2F93E180006 X-Stat-Signature: 3x4dh6rjrcbfjxmerhjmfc5bj6iiss9o X-HE-Tag: 1672159202-190515 X-HE-Meta: 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 Cj4oaNgp 6WEs8ioBOYgAe6rsPglTlRH5xSCHhUUGJPuv4S0J8XQP7ynMU1D2etMD7fA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Dec 22, 2022 at 4:47 PM Peter Xu 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