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Date:   Thu, 30 Jun 2022 15:21:35 -0400
From:   Peter Xu <peterx@redhat.com>
To:     Nadav Amit <namit@vmware.com>
Cc:     James Houghton <jthoughton@google.com>,
        "Dr. David Alan Gilbert" <dgilbert@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Muchun Song <songmuchun@bytedance.com>,
        David Hildenbrand <david@redhat.com>,
        David Rientjes <rientjes@google.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Mina Almasry <almasrymina@google.com>,
        Jue Wang <juew@google.com>,
        Manish Mishra <manish.mishra@nutanix.com>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH 00/26] hugetlb: Introduce HugeTLB high-granularity
 mapping
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On Tue, Jun 28, 2022 at 12:04:28AM +0000, Nadav Amit wrote:
> > [1] commit 824ddc601adc ("userfaultfd: provide unmasked address on page-fault")
> 
> Indeed this change of behavior (not aligning to huge-pages when flags is
> not set) was unintentional. If you want to fix it in a separate patch so
> it would be backported, that may be a good idea.

The fix seems to be straightforward, though.  Nadav, wanna post a patch
yourself?

That seems to be an accident and it's just that having sub-page mapping
rely on the accident is probably not desirable..  So irrelevant of the
separate patch I'd suggest we keep the requirement on enabling the exact
addr feature for sub-page mapping.

Thanks,

-- 
Peter Xu