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[80.230.85.71]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-4601f2f5612sm53618998f8f.15.2026.06.08.14.46.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 08 Jun 2026 14:46:32 -0700 (PDT) Date: Mon, 8 Jun 2026 17:46:27 -0400 From: "Michael S. Tsirkin" To: Gregory Price Cc: Lorenzo Stoakes , linux-kernel@vger.kernel.org, "David Hildenbrand (Arm)" , Jason Wang , Xuan Zhuo , Eugenio =?iso-8859-1?Q?P=E9rez?= , Muchun Song , Oscar Salvador , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Hugh Dickins , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Ying Huang , Alistair Popple , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Axel Rasmussen , Yuanchu Xie , Wei Xu , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , virtualization@lists.linux.dev, linux-mm@kvack.org, Andrea Arcangeli Subject: Re: [PATCH v10 12/37] mm: use folio_zero_user for user pages in post_alloc_hook Message-ID: <20260608174430-mutt-send-email-mst@kernel.org> References: <20260608154354-mutt-send-email-mst@kernel.org> <20260608161810-mutt-send-email-mst@kernel.org> <20260608170646-mutt-send-email-mst@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Jun 08, 2026 at 05:33:50PM -0400, Gregory Price wrote: > On Mon, Jun 08, 2026 at 05:16:53PM -0400, Michael S. Tsirkin wrote: > > On Mon, Jun 08, 2026 at 04:53:14PM -0400, Gregory Price wrote: > > > > > > As a start: > > > > > > 1) the user_addr and zeroing piece seems like a discrete > > > improvement worthy of its own set - aside from end goal. > > > > > > This is needed by your patch set, but was requested to > > > try to push us towards a more reasonable pattern for > > > folio_zero_user(). > > > > What I worry about is people can't agree what api they want. > > > > Oh that's just our base state of existence. We mostly agree that > all APIs are bad in some way and we don't want any of them :P > > What you're looking for is to get people to agree to the > least-offensive, least-worst option :] > > I don't think we're far off from that. I suggest doing as Zi said and > start a [DISCUSSION] thread on specifically this and lay out the needs > and wants and design issues that you've learned from the past set of > versions and continue the discussion there. > > It helps to take some snippets from your set to lay out what you've > learned and explain why you need the folio_user_zero() stuff to get from > A->Z, and then let maintainers hash out whether that should live in > post_alloc_hook or new interfaces (or outside page_alloc.c altogether). > > > I don't mind trying all kind of approaches, but it seems to > > be past the point where people feel it's costing too much of > > their time with all of these revisions. > > > > People are still commenting, so I don't think you've gotten there yet. > I think the rate of revision is what's costing too much attention. > > You'd save yourself some revisions by taking the attention you have > right now and starting the discussion thread (and consider submitting > the topic to LPC if that's something interests you!). Well it's in october, is it not? I don't think I have the patience to keep fiddling with that for half a year. > All this is to say you're doing fine, just keep on keepin' on. Maybe > pivot your approach from iterations to discussion for a bit until the > opinions settle. > > ~Gregory