From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DBDFB421EF6 for ; Tue, 7 Jul 2026 13:52:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=96.67.55.147 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783432347; cv=none; b=jCVdlvaMmVEU++/1ehegO9zCxYpD3OWBllu1dVOK7BMkR0cX43mk48TPOJz0PDMCw050/W27ICAVch051sHG4qumPR79lJa7LtFtSF+RepDFTquZF1KrII7jDLzYIM5OWOppnI87SjsoMmpnNoGU7LlLViRcRIzm4tjxCY8UKKY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783432347; c=relaxed/simple; bh=8/6KWb4PfYctYp+8gY6gHKjmETilMdBvjVRCsYZspew=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=bHSiN1SgyTadZD2hBlxH7CQ8L2bDfIKp7/w0HKlIkDDQuDM28SiCvCvZ96LxwLPytRS/8nao/MWNnTUjoCxmDwMsp1ZvLjNIvj8G/5bIkU4IccPx5T7MlF2XckvYreixeb5nnwctXrHKimW3g7pTntdKq61VeNTmJfIMVkYmprM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=surriel.com; spf=pass smtp.mailfrom=surriel.com; dkim=pass (2048-bit key) header.d=surriel.com header.i=@surriel.com header.b=l7tqum5C; arc=none smtp.client-ip=96.67.55.147 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=surriel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=surriel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=surriel.com header.i=@surriel.com header.b="l7tqum5C" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=surriel.com ; s=mail; h=MIME-Version:Content-Transfer-Encoding:Content-Type:References: In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=8/6KWb4PfYctYp+8gY6gHKjmETilMdBvjVRCsYZspew=; b=l7tqum5CgVXYfcPwtJgTxfXiNY W+Xf+yjP5ugU2fn6LRQhGIG/KXGwZERlBynLMOA5aHPAjPSm5S6XBF3IDbi0TJyAThoasln5kjxAo beip/tuPnL3fLnGzJwLunkBGhyRftaYswtsTi2VOxFgEx5xtCC1s0eg4v8B8L3/mu6ZGXGnn8Qs0o 7nA3r1DP6GorvKH3z0hsuJe5qn6HyVDyQ4ujI5wkoVj7IXEhvFsNvBZ1gvc0rVeL3xWODUBHM+A3z 43wWN0u9A6AYoIpZ0/zbIr6ngSv8NaivanmsvSjuWuYwacUBuYRn+hlNll3yL8lQ0Ndj5T8P3iNwh jBQJOKdg==; Received: from fangorn.home.surriel.com ([10.0.13.7]) by shelob.surriel.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.97.1) (envelope-from ) id 1wh6DV-000000002t1-1k1i; Tue, 07 Jul 2026 09:52:05 -0400 Message-ID: <5c06c0ad2f2a7a039181a1775623ec06ca063dff.camel@surriel.com> Subject: Re: [PATCH 2/3] mm/pagewalk: let folio_walk_start() run under the per-VMA lock From: Rik van Riel To: Lorenzo Stoakes Cc: linux-kernel@vger.kernel.org, x86@kernel.org, linux-mm@kvack.org, Thomas Gleixner , Ingo Molnar , Dmitry Ilvokhin , Borislav Petkov , Dave Hansen , Andrew Morton , David Hildenbrand , "Liam R. Howlett" , Vlastimil Babka , Suren Baghdasaryan , kernel-team@meta.com Date: Tue, 07 Jul 2026 09:52:05 -0400 In-Reply-To: References: <20260625015053.2445008-1-riel@surriel.com> <20260625015053.2445008-3-riel@surriel.com> <610d1c95a2f9131d5c018304f9a90afb33e8a032.camel@surriel.com> Autocrypt: addr=riel@surriel.com; prefer-encrypt=mutual; keydata=mQENBFIt3aUBCADCK0LicyCYyMa0E1lodCDUBf6G+6C5UXKG1jEYwQu49cc/gUBTTk33A eo2hjn4JinVaPF3zfZprnKMEGGv4dHvEOCPWiNhlz5RtqH3SKJllq2dpeMS9RqbMvDA36rlJIIo47 Z/nl6IA8MDhSqyqdnTY8z7LnQHqq16jAqwo7Ll9qALXz4yG1ZdSCmo80VPetBZZPw7WMjo+1hByv/ lvdFnLfiQ52tayuuC1r9x2qZ/SYWd2M4p/f5CLmvG9UcnkbYFsKWz8bwOBWKg1PQcaYHLx06sHGdY dIDaeVvkIfMFwAprSo5EFU+aes2VB2ZjugOTbkkW2aPSWTRsBhPHhV6dABEBAAG0HlJpayB2YW4gU mllbCA8cmllbEByZWRoYXQuY29tPokBHwQwAQIACQUCW5LcVgIdIAAKCRDOed6ShMTeg05SB/986o gEgdq4byrtaBQKFg5LWfd8e+h+QzLOg/T8mSS3dJzFXe5JBOfvYg7Bj47xXi9I5sM+I9Lu9+1XVb/ r2rGJrU1DwA09TnmyFtK76bgMF0sBEh1ECILYNQTEIemzNFwOWLZZlEhZFRJsZyX+mtEp/WQIygHV WjwuP69VJw+fPQvLOGn4j8W9QXuvhha7u1QJ7mYx4dLGHrZlHdwDsqpvWsW+3rsIqs1BBe5/Itz9o 6y9gLNtQzwmSDioV8KhF85VmYInslhv5tUtMEppfdTLyX4SUKh8ftNIVmH9mXyRCZclSoa6IMd635 Jq1Pj2/Lp64tOzSvN5Y9zaiCc5FucXtB9SaWsgdmFuIFJpZWwgPHJpZWxAc3VycmllbC5jb20+iQE +BBMBAgAoBQJSLd2lAhsjBQkSzAMABgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIXgAAKCRDOed6ShMTe g4PpB/0ZivKYFt0LaB22ssWUrBoeNWCP1NY/lkq2QbPhR3agLB7ZXI97PF2z/5QD9Fuy/FD/jddPx KRTvFCtHcEzTOcFjBmf52uqgt3U40H9GM++0IM0yHusd9EzlaWsbp09vsAV2DwdqS69x9RPbvE/Ne fO5subhocH76okcF/aQiQ+oj2j6LJZGBJBVigOHg+4zyzdDgKM+jp0bvDI51KQ4XfxV593OhvkS3z 3FPx0CE7l62WhWrieHyBblqvkTYgJ6dq4bsYpqxxGJOkQ47WpEUx6onH+rImWmPJbSYGhwBzTo0Mm G1Nb1qGPG+mTrSmJjDRxrwf1zjmYqQreWVSFEt26tBpSaWsgdmFuIFJpZWwgPHJpZWxAZmIuY29tP okBPgQTAQIAKAUCW5LbiAIbIwUJEswDAAYLCQgHAwIGFQgCCQoLBBYCAwECHgECF4AACgkQznneko TE3oOUEQgAsrGxjTC1bGtZyuvyQPcXclap11Ogib6rQywGYu6/Mnkbd6hbyY3wpdyQii/cas2S44N cQj8HkGv91JLVE24/Wt0gITPCH3rLVJJDGQxprHTVDs1t1RAbsbp0XTksZPCNWDGYIBo2aHDwErhI omYQ0Xluo1WBtH/UmHgirHvclsou1Ks9jyTxiPyUKRfae7GNOFiX99+ZlB27P3t8CjtSO831Ij0Ip QrfooZ21YVlUKw0Wy6Ll8EyefyrEYSh8KTm8dQj4O7xxvdg865TLeLpho5PwDRF+/mR3qi8CdGbkE c4pYZQO8UDXUN4S+pe0aTeTqlYw8rRHWF9TnvtpcNzZw== Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Tue, 2026-07-07 at 13:24 +0100, Lorenzo Stoakes wrote: >=20 > And on page table retraction, importantly, the PMD entry is cleared > _with > the PTE PTL held_, e.g. in retract_page_tables(): >=20 Ahhh! That's the part I was missing. Thank you. That simplifies things nicely. --=20 All Rights Reversed.