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t=1788885060; bh=PbREINwiHzdfOIDyvzXmpqXBcn2ufYLyhPRpYbuszSY=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=JJhwsDAzdDYYBuw+OjApzid/DL+uKEvAJ2ThGvEQEp2/vT/ZgMLMANci4KhIZVs+q KJIDDQQEyY89H+5OdaSGpu84eRh3LwQimAoVYTdEGIr2HH6/9L/SixMgZ/eRkkp52m HbFatySDrHgffwcdSMmR1TKgUfv7D8u8QNU9vBBvQDD5ag/tdudXWiBGWJIgqhyP20 DUX/YejlKToKQSDWX24HIZrv5PvbQhTnV/ykAxojd5wB18HHVIGHuG5DUbmadoVHmP tLQYD8brxV8cRvpS+E2sUT9aaSJuO4XG6dBrT5eWlTQggVrvOdfVg8KQSmvc6cdwZ6 xhu0OCpOAfQuQ== Message-ID: Date: Tue, 8 Sep 2026 18:30:50 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 03/25] mm/fbatch: temporarily disable lazyfree and mlock+munlock batching Content-Language: en-US To: Hugh Dickins , Andrew Morton Cc: Ackerley Tng , Alexander Viro , Baolin Wang , Barry Song , Binbin Wu , Christian Brauner , Christoph Hellwig , Christoph Lameter , Claudio Imbrenda , David Hildenbrand , JP Kobryn , Jan Kara , Jens Axboe , Johannes Weiner , Kairui Song , Kiryl Shutsemau , Lance Yang , Leonardo Bras , Lorenzo Stoakes , Marcelo Tosatti , Matthew Wilcox , Mel Gorman , Miaohe Lin , Michal Hocko , Minchan Kim , Muchun Song , Oscar Salvador , Peter Zijlstra , Qi Zheng , Rik van Riel , Sebastian Andrzej Siewior , Shakeel Butt , Suren Baghdasaryan , Yang Shi , Yu Zhao , Zach O'Keefe , Zi Yan , linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <14a16945-529b-8bc0-ab38-3ea97e54e223@google.com> <9593975e-8732-999a-73d1-37fd332eb840@google.com> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 68B1BC0013 X-Stat-Signature: q1ruzbmz3413uicfoc3t98m937bm45ax X-HE-Tag: 1788885061-518679 X-HE-Meta: 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 fYQ63M6Q K29isXjtqsBAXcHbXTdNRi17fQPQdRiK9WqowWNH2sTYc+i9BvPJd72uScOuF6lhocwjt53W7gjw5uLPZzXozOCCC/CZJZDAgU2TMWkivDHVFNDhZRbJtEyHHhUj1I5sdEWJuNcY9aZuMB89qBB8haFpPA8yvR+FddE4dYfzKJNFWCgTizChbBa0iHw0qRqzpSfWuXefvhcFlbryhDOPKhHLHCOr9vWbQIREEYvrIEjGskHoi6nSJSSSNQP4HFzjAZxR54EW9HFXoLc9PDstf1NXUPL8xWQ6kcN6IbUWjFxPOUwJZrCWGiWDZlmgfJa8dvdWqmkwWKlu+LUX/GI7byGfwicmb4+aUlQd4dVRC9nfOuhTUWBzmVHh7NRrtTFngQF39 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 8/24/26 15:58, Hugh Dickins wrote: > It will not matter if we occasionally get activation or deactivation > wrong; but a mistaken lazyfree (MADV_FREE) would likely cause dataloss. > So disable its batching while reworking the per-cpu fbatch handling, > then re-enable it with more thought afterwards. > > Similarly disable mlock+munlock batching temporarily: they will need > some redesign before re-enabling. Just insert one disabling line for > now, leaving the rest of the code as it was, for consideration later. > > Signed-off-by: Hugh Dickins Reviewed-by: Vlastimil Babka (SUSE)