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a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774465727; bh=Qo41yGMXvFJziS9alU9r9/+sGjFxjt4T2tB+BRTnfmI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=M6BRRpGNU+l+t/1WP2LzJARmGEBxhq/iSy4M7oAGkbTjXmU+7qIXz/CXlnURUJZDs TGHiVbNkwtNLGM2foEPW7gFvzL+zlA2JZTkKG+Q5FGEMO1FI89Z3WEDMAStSUc+JKL Ut+u74RH6/EzWcvqBk0QYi0qAmEcXOxXPqPz0LCgZHn7kC1xF4jSygmwAhJM3YncyC GKdiuUAefSRfuhb9BQtP2ajY2FAC1p1bdLzeAu8Da0y3ym91sFhk0oic+nqgklU0GB V/KCvC/5WKUJcxtJAaeqin4+SifD9kCzGujMle1it0FmoUZA4DRuPy80iF13OiKmpb 7cLwwhH1VvjzA== Date: Wed, 25 Mar 2026 21:08:38 +0200 From: Mike Rapoport To: "David Hildenbrand (Arm)" Cc: Jianhui Zhou , SeongJae Park , Andrew Morton , jane.chu@oracle.com, Muchun Song , Oscar Salvador , Peter Xu , Andrea Arcangeli , Mike Kravetz , Hugh Dickins , Sidhartha Kumar , Jonas Zhou , linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, syzbot+f525fd79634858f478e7@syzkaller.appspotmail.com Subject: Re: [PATCH v4] mm/userfaultfd: fix hugetlb fault mutex hash calculation Message-ID: References: <20260324170311.dc5b54fe0765f2e680e3cc90@linux-foundation.org> <20260325010618.85366-1-sj@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: m3spkm11xi9ff38ars57jkrzopiay5f4 X-Rspamd-Queue-Id: DF4CF18000A X-Rspam-User: X-Rspamd-Server: rspam03 X-HE-Tag: 1774465728-927416 X-HE-Meta: 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 GKTPZ3Ie mnq31bdtcCAydonlvB9FzsLBIOgnHRCrhzlLXNHu5TROkKNZRH/vn62gjpFETsVoTbKaxfBNPXHN29PLTSD5OodJAmv0y16FXOp5zc6KixLtYqGQrDuZkoeu/orTU8kR1EY/NPxCp5RWzE08sNE3j+JhKVLjs8Y/10A9R1AXuxKLVu8gCD6DhuVC4q5FcnBpYOM/OBEaPI5N2rRZqNkD7FKLz0IJtUl7CV2AnsEtVR0fsuvISgO+69B/hshk7Ynp1XOQhx+wyWTfSC29xrlLsPl002nkzbbi+cdQ3EvBPwbfCUt0qzVwlGqtL/Nq8vYL/QcEKmGhOgjQmoDAp9RgpLhRFmoL20+uN8aOE Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Mar 25, 2026 at 09:49:54AM +0100, David Hildenbrand (Arm) wrote: > On 3/25/26 07:07, Jianhui Zhou wrote: > > On Tue, Mar 25, 2026 at 01:06:00AM +0000, SeongJae Park wrote: > >> Seems userfaulfd.c is the only caller of the new helper function. Why don't > >> you define the function in userfaultfd.c ? > > I kept hugetlb_linear_page_index() in include/linux/hugetlb.h because > > this is hugetlb-specific logic, not userfaultfd-specific logic. > > Yes, and see my comment about either removing it entirely again next, or > actually also using it in hugetlb.c. I think it's better to move large piece of mfill_atomic_hugetlb() to hugetlb.c and git rid of the helper then. And now keep it simple for easier backporting. > -- > Cheers, > > David -- Sincerely yours, Mike.