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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 13871C98310 for ; Wed, 23 Sep 2026 19:53:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 016406B008C; Wed, 23 Sep 2026 15:53:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id EE2736B0092; Wed, 23 Sep 2026 15:53:38 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DAE456B0093; Wed, 23 Sep 2026 15:53:38 -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 A11F96B008C for ; Wed, 23 Sep 2026 15:53:38 -0400 (EDT) Received: from smtpin25.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 1353A808E2 for ; Wed, 23 Sep 2026 19:53:38 +0000 (UTC) X-FDA: 85246076916.25.5B004F3 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf09.hostedemail.com (Postfix) with ESMTP id 2CE48140004 for ; Wed, 23 Sep 2026 19:53:36 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=eE9WCS2o; dmarc=none; spf=pass (imf09.hostedemail.com: domain of akpm@linux-foundation.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1790193216; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=p4edf0YYCmWA79RL5zC8Xmz8p09vaatBemczrDrD/n0=; b=0QxBuYEIc9dANENEceVENmEsrPLlCh9jtKGjHkFSa3CHeqH+hGdVHlsW6hanqEMTlETJm7 WrtWImHViaJlRdsyqs+fulAS4BQoHN8Nl0/GgMbH/DRwN7srGcdMSHkuYHseLQ5AaCVVuJ eQ4iy1e0pQvVfoOnF9nM4CeD1EuGRrc= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=eE9WCS2o; dmarc=none; spf=pass (imf09.hostedemail.com: domain of akpm@linux-foundation.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1790193216; b=lAb6OWjPtie+LY6DvL8V7/pdXkYX5IEeD2B9fwAn5T6WlYgJpX19jWhW7HQ7TUbFYrpiEB kZrcGay6A2WmyIQsC5T38eJsaK55sf4eUZJFFsmDYsTLdSEwFBQqy6ZayL/Db3fJ3qWvW5 piKAkB0+rFpn/ocMyQjiWO8wJAoh/gY= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id A726741A56; Wed, 23 Sep 2026 19:53:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AF0D01F000FF; Wed, 23 Sep 2026 19:53:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1790193214; bh=p4edf0YYCmWA79RL5zC8Xmz8p09vaatBemczrDrD/n0=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=eE9WCS2ousaSTQemTQ4AA1ZkY9n6f+r4xISLZALK3AMHEPFEmixpwYev88YxZLXeN CHmB0H3Bw3SM8Ql9Z+14bUyIFrP0hgQ5aVwbxlPcF2pYaWAyJOWebDVlGCFrkFZrGM ck3P7oheu0DSTRvd14VSbm/sP0AV2Mko/VrdoIFk= Date: Wed, 23 Sep 2026 12:53:31 -0700 From: Andrew Morton To: "Lorenzo Stoakes (ARM)" Cc: David Hildenbrand , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Kiryl Shutsemau , Guo Ren , Brian Cain , Geert Uytterhoeven , Dinh Nguyen , Simon Schuster , Jonas Bonn , Stefan Kristiansson , Stafford Horne , Rich Felker , John Paul Adrian Glaubitz , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Russell King , Vineet Gupta , Michal Simek , Chris Zankel , Max Filippov , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Peter Zijlstra , "David S. Miller" , Andreas Larsson , Richard Henderson , Matt Turner , Magnus Lindholm , Catalin Marinas , Mark Rutland , Huacai Chen , WANG Xuerui , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Madhavan Srinivasan , Michael Ellerman , "Christophe Leroy (CS GROUP)" , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Richard Weinberger , Anton Ivanov , Johannes Berg , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Arnd Bergmann , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jason Gunthorpe , John Hubbard , Peter Xu , Yoshinori Sato , Shakeel Butt , Jonathan Corbet , Randy Dunlap , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-snps-arc@lists.infradead.org, linux-arch@vger.kernel.org, sparclinux@vger.kernel.org, linux-alpha@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-um@lists.infradead.org, Hugh Dickins , Qi Zheng , linux-doc@vger.kernel.org Subject: Re: [PATCH v4 01/12] mm/khugepaged: deposit a newly allocated page table on collapse Message-Id: <20260923125331.882dfeb1f43d284b146a4633@linux-foundation.org> In-Reply-To: References: <20260922-rcu-pagetable-freeing-v4-0-fe1ad1f1e303@kernel.org> <20260922-rcu-pagetable-freeing-v4-1-fe1ad1f1e303@kernel.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: jo9dnn54wd5go8kg995yiujmm8fmbeqg X-Rspam-User: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 2CE48140004 X-HE-Tag: 1790193216-551856 X-HE-Meta: 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 ogX8Bsi0 g7I6YIinnDloumj1diOaks7dt6Upefv/aiK2nzjUHQfcRgLwQacbdHy3mIt7ULrh1rALwhQZuALYf2GtqCEZHL9vMEd0jgtxo7oqPTgMsZPJPgkDvILxzHjxDLxrpnWloR/Gjz53jg7x0Feg0xXeIo9MizYt32RP2yBs3NZ4WM895C/M/qlfpMbMzKkZtbufWWba92AXiRCRvL9n/xkASHk6GFEIbqI6kY5Aa7roIYr1ncOJeXYO/0QN3WyZSptwIaZD/mGzb95rkxgsZ3eH7npw/1dq1SCNYUaTYA5ZFoC8xJaDCfW1bQg/3Te2k/jSxnsyCpBITS4i1GInRcRXdDCpRk5Z08JJAWSyQ Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 23 Sep 2026 08:14:01 +0100 "Lorenzo Stoakes (ARM)" wrote: > Andrew - would it be possible to make one quick fix up below? > > Fixup is here: > > - if (!pgtable) > - goto out_nolock; > + if (!pgtable) { > + result = SCAN_ALLOC_HUGE_PAGE_FAIL; > + goto out_nolock; > + } --- a/mm/khugepaged.c~mm-khugepaged-deposit-a-newly-allocated-page-table-on-collapse-fix +++ a/mm/khugepaged.c @@ -1329,8 +1329,10 @@ static enum scan_result collapse_huge_pa if (is_pmd_order(order)) { pgtable = alloc_deposit_pte(mm); - if (!pgtable) + if (!pgtable) { + result = SCAN_ALLOC_HUGE_PAGE_FAIL; goto out_nolock; + } } mmap_read_lock(mm); _