From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.subspace.kernel.org (Postfix) with ESMTP id CCBDF606A329 for ; Thu, 29 Oct 2026 13:15:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=MmZFJDiu Received: by kanga.kvack.org (Postfix) id EEA6C6B05B6; Thu, 29 Oct 2026 09:15:48 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E9BE46B05B7; Thu, 29 Oct 2026 09:15:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DB39F6B05B8; Thu, 29 Oct 2026 09:15:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id BC6DF6B05B6 for ; Thu, 29 Oct 2026 09:15:48 -0400 (EDT) Received: from smtpin28.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 49609A7E33 for ; Thu, 29 Oct 2026 13:15:48 +0000 (UTC) X-FDA: 85375711176.28.EDD5F70 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf14.hostedemail.com (Postfix) with ESMTP id A277A100011 for ; Thu, 29 Oct 2026 13:15:46 +0000 (UTC) Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=MmZFJDiu; spf=pass (imf14.hostedemail.com: domain of pratyush@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=pratyush@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1793279746; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=lqh2h9OdAhEsv8R7JgV92DMgdxSdmNya/U3mKn63VeQ=; b=44RGKhUOwmymP56OrD9cwZfBMhj4lWWOBpl1UVbmRDHu8+utJH0ZCaoJMKTsQB+FN2iiXT B57bLB58uJhAXkx30DRMTNYuiQLI7XsqFh7zosLQznCEP0emtXp+wZqsHSaxWTkqFaK6ga lPSAlLBvFiaye7pURjja8pimpb5yYDE= ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1793279746; b=7EdE1nbpc8QUN3UAdMShv7lrv/5akV81uTgREKnGm57IOc3MYk+CiMiUjWmEBZp7uNIktT gbE/eFJkbbDsO7Zp5kPcEM/346BYh6YPZ0Ze0vDETEQPGhISdb2spG5oyXq3nlL1A9gFc3 SMSnl80HZe3WlfuNajQfOmGpA8rnEa4= ARC-Authentication-Results: i=1; imf14.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=MmZFJDiu; spf=pass (imf14.hostedemail.com: domain of pratyush@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=pratyush@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id DF0D6600D1; Thu, 29 Oct 2026 13:15:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A98C01F01825; Thu, 29 Oct 2026 13:15:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793279745; bh=lqh2h9OdAhEsv8R7JgV92DMgdxSdmNya/U3mKn63VeQ=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=MmZFJDiu5p0O+/D6H9EcM1bWgs2P1sLao6pof6JMiCUbkuDuhoUnWvIYq6wdOTfbm BpcdU9h8weFSI7YLOAuJPhsKw4Gi4YRQO5cUZN10fGi7ReIbYh9hagBT+jrYElX2YH +ih3xGMrA3kLoEpG35T95VY9VY8CZ9PitTQpY1G0Ri8tbgIY4OEyb5lujXrodMB0ht 9mq4mqJBN5iSIEzqMYOWBi7auC6ctfTuZZc8lG2Ic63rca7gBPiLKOXjhv0fOpMgDy ZaqKgfNBg3F6hiO66BQ6fFngZ+rT7A9j651kIkx8sefoDuBSSHj73PbusVG/D+GcyR U4/gnsox7yWQw== From: Pratyush Yadav To: Pasha Tatashin Cc: Pratyush Yadav , Alexander Viro , Christian Brauner , Jan Kara , "Matthew Wilcox (Oracle)" , Hugh Dickins , Baolin Wang , Andrew Morton , David Hildenbrand , Zi Yan , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Kiryl Shutsemau , Mike Rapoport , Matthew Brost , Joshua Hahn , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Kairui Song , Qi Zheng , Shakeel Butt , Axel Rasmussen , Yuanchu Xie , Wei Xu , Baoquan He , Johannes Weiner , Michal Hocko , Lorenzo Stoakes , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kexec@lists.infradead.org Subject: Re: [PATCH 1/3] mm/memfd_luo: don't use memfd_pin_folios() In-Reply-To: (Pasha Tatashin's message of "Wed, 28 Oct 2026 20:01:59 -0400") References: <20261027173031.763213-1-pratyush@kernel.org> <20261027173031.763213-2-pratyush@kernel.org> <179321872100.1775665.6881420026761127422.b4-review@b4> <2vxz4ie5o2ak.fsf@kernel.org> Date: Thu, 29 Oct 2026 14:15:38 +0100 Message-ID: <2vxzv76kmyv9.fsf@kernel.org> User-Agent: Gnus/5.13 (Gnus v5.13) X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: A277A100011 X-Stat-Signature: ydw173yeo68xpw8mjggex8yyfuoiea9f X-Rspam-User: X-Spam-Status: No, score=-12.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=4.0.1 X-HE-Tag: 1793279746-583199 X-HE-Meta: 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 Zoi+POl1 9VoRXMx3p3zRh+7SPJbwxbIcMIUoLH71slIxBqriNxvQo4R5Y5VHUg1+DFApAzD84juPojo2Xr36RAvH9cvWEVLg1ZBH6gH90wkm+mvCvjgHnKki1uFuw1mAeMJGyjv6R3vmkbN0939LLt2Hs2P9PUW56NfED1PoFxdexUr0YKYSmi357NK2Er3V+B8yVBGXQ2zsqkd2ZYIRywD3/GRKK+1B35AbeGlJBfeiGhmEs9GQgWTKFPqpREQ1bW7vWn79rrdVSBO/zndhLcETWIktkn6JFa8OBSsKnLjFk0l4oTx3aDr37pixq3pL8a7PliFS7Rp6M/Q8Rymvrljf/vmQDLNFGPHHgdFvtHsgO6RvQCSPVt/nbjucnNUhkhulgwvfucjxmPAe9sQb8dkojCt/cA+7XJYM+dHLjpIH3OcqC1C2pEamJ40jZ5PgtEw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Wed, Oct 28 2026, Pasha Tatashin wrote: > On 10-29 00:04, Pratyush Yadav wrote: >> > Nit: >> > >> > I would suggest adding another helper, memfd_luo_get_folio(inode, index, >> > &folio), that wraps: >> > >> > - shmem_get_folio() >> > - The !folio_is_longterm_pinnable() migration retry loop logic >> > >> > I think this would make the final code a bit more manageable. >> >> Sounds good, will do. >> >> > >> > Other than that the patch looks alright, feel free to add >> > Acked-by: Pasha Tatashin >> > Once the nit is addressed. >> >> Thanks! >> >> I think the MM side might take some time to gather reviews so I will >> send this out as part of a liveupdate-only series. This patch is useful >> on its own anyway. > > Sounds good. Could you also consider adding a patch to that live > update-only series to extend the memfd freeze from retrieve to finish()? > That would close another gap that does not affect us yet, but will once > other session fds depend on the memfd mapping. > > See: > https://lore.kernel.org/r/20261022225035.377445-8-dmatlack@google.com Hmm, right. That's a useful fix. I think I'll do that in a separate series, since it can go independently. -- Regards, Pratyush Yadav