From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 25C22C61CE8 for ; Thu, 12 Jun 2025 18:02:54 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 8C5EE6B00A2; Thu, 12 Jun 2025 14:02:54 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 89E156B00A3; Thu, 12 Jun 2025 14:02:54 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7B3C66B00A4; Thu, 12 Jun 2025 14:02:54 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 5BFCD6B00A2 for ; Thu, 12 Jun 2025 14:02:54 -0400 (EDT) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 01C76141924 for ; Thu, 12 Jun 2025 18:02:53 +0000 (UTC) X-FDA: 83547519468.07.8594837 Received: from mail-qv1-f51.google.com (mail-qv1-f51.google.com [209.85.219.51]) by imf06.hostedemail.com (Postfix) with ESMTP id 00CFB180008 for ; Thu, 12 Jun 2025 18:02:51 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=ziepe.ca header.s=google header.b=X0FI0Esy; dmarc=none; spf=pass (imf06.hostedemail.com: domain of jgg@ziepe.ca designates 209.85.219.51 as permitted sender) smtp.mailfrom=jgg@ziepe.ca ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1749751372; 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=GDDRWPX1lH08t+vNjXng50l3/jIs9pZf702xFyzNrfY=; b=hN2oj3F6Rtx/OI2bvlCxBTQKX+bESsBWn3Z7+pXD8Zr75aRVM6+nCuVAnv34PoCNycFDaq wtMkZvnVv5RIUW25Ct+2ZXl/JYSce1KBybsfSkbQYx+M79HuitheLFh05ECpPDEPc+k7RN 2IzK3sQMmD8ZxB6FhLPmwBYIF4ZOcHQ= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=ziepe.ca header.s=google header.b=X0FI0Esy; dmarc=none; spf=pass (imf06.hostedemail.com: domain of jgg@ziepe.ca designates 209.85.219.51 as permitted sender) smtp.mailfrom=jgg@ziepe.ca ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1749751372; a=rsa-sha256; cv=none; b=c1nOFx0EOl/JaXvX13HnujkCPssTKma90jlixYQUcG0nxOspPHLR+zChZWyXlaOnuanY2c wRoFa/43mVaW2gClUYXu8WjpdW7pRDuD9xgQVKNRK5I5mTXwwtdEnGaXDwo7dqZWjs+ZY0 xbtnwnKOX+UhU1fHEWTwbCl1ED99/2I= Received: by mail-qv1-f51.google.com with SMTP id 6a1803df08f44-6faf66905baso19202136d6.2 for ; Thu, 12 Jun 2025 11:02:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1749751371; x=1750356171; darn=kvack.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=GDDRWPX1lH08t+vNjXng50l3/jIs9pZf702xFyzNrfY=; b=X0FI0EsyCMBXTIB3GNzIYkNglA4XHJzvbtGY0YFbJ6KKvhA3Y8BBniIOG1r/C73J0f VrLFqBpMKKv2S+lKWVkAIDbQ19+0WJ5XaqIg0/0/36Jfpc6SjgXSxTgltCH4HnPz8Mwn ZaBb2HH6npoOtm3ayNbQHmhvSnfqUT97P2dUWFWFBJs4/Dn5CSKK4cnzP1Le3+x0pj+F 7uEl7pG6rDO9soNe5O31gttdRb+WJ59pnv7uY/ZRER1ymGudvrZEDK6FL7qToBs57U7k KyuY8u2vLifeFJffHh07+XtCrCouOIyYeqbNa9+CSDdo2XLGOXgiT/ACHBrj4CxL8hpU JogA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1749751371; x=1750356171; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=GDDRWPX1lH08t+vNjXng50l3/jIs9pZf702xFyzNrfY=; b=GzrDEvQ08qi4Lc0P9hLJ4FWCpwZExJ+pYjIE5EsptakJZv072bw3ufOq03Ana60NO1 D5f1cPVRv6a0NkwRfSF8zpm+LCj4sov9rtRI5mtPiRp9MOlejPldLRbnpbx2UOfoFfNh dXSYg1LDYd4b+pCzcAYcUVkjybJUMrSjhD8iHUyaATH5JBZ9ll6oBKkbPm2MqXduUjKX g2P7klOGYLOigKs4KUa7w96AmWGmYlS7DhMgW0/ZLtGHJWYX5ByV3jaZuRf7Y84kP6Vr YN0JhEm4v+hkZ0uzkIEaPL/uz8vSzRH6nuDimPcpcIS1Q+HGwKzC42XCj1EHuD9JmSHT srLw== X-Forwarded-Encrypted: i=1; AJvYcCXAPjt0oNULfYAhAWHX7p/NEvs9zwoEWbX3nHDRIi9YorkcuJGg/PThS3wwxePcwG1KC2Xtx8TIZQ==@kvack.org X-Gm-Message-State: AOJu0YykoTj3o/zIqTMBQ1blQU1G3+VqX3a2gWzcmYzCbxGDnlxJXuV3 NFbcGsADocpmVHwq5bYZIPqkUGmDEPzeTbzqLqCaAUJ9ry2UvU42o9EUJ82ik/3fDW0= X-Gm-Gg: ASbGncsnqhYzb9pECQzk9d8/lkg3jzymL5iTwbPUsn3Oo1M2V4TLJIek3GdOmFfEnLf RoUjmjIB6uC9ps3thbF15K/a1XU1xEP9h9jZxeWsrgOZi3j5drkH6st6sPv0wbxwLpYClulDc2O WrY2CSf+Jo1HT/3G7KR71i6IelxlzztrBcjQe+UGqfDHQZtsH+gkqXmcwuNaC8SMCROVWuNrnj+ NvoJFOzXKOLErBifyo3nnHRqtJKbF7N5WAImEXc7NTlzkXn1fsEwgYsrHsTnJ0SVKNlkUygUAbz 13RMvez+RliV2G4B5klfravz4RplgcpF7rgRnlFW6/UqtBBMds+ldlO9gPXfBnFvZKAMfZmx2PQ skHPfsr4nEV1GF/FFWnAlXwn6AppQqJSKKMs8wQ== X-Google-Smtp-Source: AGHT+IErLirqZ/IjWI/XgEsozLii1/UP6Pds6ZK0pCCFWbV1P+4pjEqskuPc1d9m/qNp3cmq3DvELw== X-Received: by 2002:a05:6214:e86:b0:6fa:d95d:d0b1 with SMTP id 6a1803df08f44-6fb3d2b2155mr7744516d6.24.1749751371067; Thu, 12 Jun 2025 11:02:51 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-142-167-56-70.dhcp-dynamic.fibreop.ns.bellaliant.net. [142.167.56.70]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-6fb35c8ee5fsm12595756d6.122.2025.06.12.11.02.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Jun 2025 11:02:50 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1uPmGI-00000004kgd-0Li5; Thu, 12 Jun 2025 15:02:50 -0300 Date: Thu, 12 Jun 2025 15:02:50 -0300 From: Jason Gunthorpe To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, Andrew Morton , Alistair Popple , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Dan Williams , Oscar Salvador Subject: Re: [PATCH v2 3/3] mm/huge_memory: don't mark refcounted folios special in vmf_insert_folio_pud() Message-ID: <20250612180250.GC1130869@ziepe.ca> References: <20250611120654.545963-1-david@redhat.com> <20250611120654.545963-4-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250611120654.545963-4-david@redhat.com> X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 00CFB180008 X-Stat-Signature: ykcejhgpuusn9wkwfp35xfm73rir4gdi X-Rspam-User: X-HE-Tag: 1749751371-565978 X-HE-Meta: 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 xZ8AaoCa h2OEi7d3FZeS9e93UJ+AFLWIfBUYeFlDxsb10kZu62SNeztRIGNxunjmm94U3Lx5Vg6SB3n+iig7schTjTh2bPDQ4nRjekpC1ojFfYKjgQVm/ucVFEvHyRl+XBMunikKaKYzmrLljBHVmmMVYdd4t+dSxQnf0iSDUnK0cA0P+chHplg9fxRJfAtG+Y/eG6WdFqQ19YpsswPfsoP5NZRIHPxtZIUp6pTjCe45XHDw7tak2obxc/xPo0IjrQ34sNIop108egkThYZTJKGpNMzM1JVex3KOKo4RUrwMcFoi6ipB7ZOiBKTzckhgi7IZnkROeILEW5OHlQUX1trgk1Ii2XPlwOUBd02mtm4HP68SgjP8llm5UAXIDT/9MH8qfZN1r+H1F X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Jun 11, 2025 at 02:06:54PM +0200, David Hildenbrand wrote: > Marking PUDs that map a "normal" refcounted folios as special is > against our rules documented for vm_normal_page(). > > Fortunately, there are not that many pud_special() check that can be > mislead and are right now rather harmless: e.g., none so far > bases decisions whether to grab a folio reference on that decision. > > Well, and GUP-fast will fallback to GUP-slow. All in all, so far no big > implications as it seems. > > Getting this right will get more important as we introduce > folio_normal_page_pud() and start using it in more place where we > currently special-case based on other VMA flags. > > Fix it just like we fixed vmf_insert_folio_pmd(). > > Add folio_mk_pud() to mimic what we do with folio_mk_pmd(). > > Fixes: dbe54153296d ("mm/huge_memory: add vmf_insert_folio_pud()") > Signed-off-by: David Hildenbrand > --- > include/linux/mm.h | 19 ++++++++++++++++- > mm/huge_memory.c | 51 +++++++++++++++++++++++++--------------------- > 2 files changed, 46 insertions(+), 24 deletions(-) Reviewed-by: Jason Gunthorpe Jason