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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0AC19CA5FDD for ; Fri, 2 Oct 2026 12:27:12 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4hx7MM3ybzz2ygK; Fri, 02 Oct 2026 22:27:11 +1000 (AEST) Authentication-Results: lists.ozlabs.org; arc=none smtp.remote-ip="2600:3c04:e001:324:0:1991:8:25" ARC-Seal: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1790944031; cv=none; b=LHHcsWS9OucsPTN9gRYlK7Fy4TGpCVvZpkOOxl1pD39rRp0KN49eqKK75nJMCZbHFowWqyju7MdzabKCEGS7PXCGGcGrwjk/1G4nSYx3Q+CXPHyj4KHCKrb/9b6Y9L+a/D1IOUb0KyFklr6MdMrIg5FghYFZ4BWrJ31yqTQKD+kPLjX+IWoVOvXEbuk/6kD40fKjecKRrlgF/4IaRnvRZ8gU+q3mFqq2NVZf36SfO6bGryPAJBa6OMn3GzaftG4kuBBfOPbWUw7VxSDTznkvoMYhvLKeXiiNUoDWxym1rJBNSI8lfJqzzg1roD7etkn0Z8TeBwbOCQd/65EtjaJNHQ== ARC-Message-Signature: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1790944031; c=relaxed/relaxed; bh=hHcwGbw/dTLavCD1q0Wz915FUcvfzunoMb3D7u+JUi8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=iwm1T+XDM9DZLk+ti1GmDZ8TXM+7s3RVZn8or/ZR0xUaj6VC++yRuG3Qu9uED8nGF72DiV8qdkdyikpVM/M51XTb90l7OxU6eEChBZi0t+93L3dkhlfL08kHszl4JolduUDjA0byrKtPrDWlSjBCEdxKrdc1jeCae1e8f6nMnwcDmPKqLlgQwsumsJNX5qZGKlYT4WvTcFdMhb5si1vKGj0SNzbNYogxS2w/7sWmjEEl608Vx2G+OAzmKBaRR9R2nkVFrjLOycdFl8o2lCaXIYaPg5Z6nBWnzZw0yjtF351OlTjVWA1MXLaczzEfon8tqcC5zoK7QuLwojW0lq2eeA== ARC-Authentication-Results: i=1; lists.ozlabs.org; dmarc=pass (p=quarantine dis=none) header.from=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=cxL+MpzC; dkim-atps=neutral; spf=pass (client-ip=2600:3c04:e001:324:0:1991:8:25; helo=tor.source.kernel.org; envelope-from=ljs@kernel.org; receiver=lists.ozlabs.org) smtp.mailfrom=kernel.org Authentication-Results: lists.ozlabs.org; dmarc=pass (p=quarantine dis=none) header.from=kernel.org Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=cxL+MpzC; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=2600:3c04:e001:324:0:1991:8:25; helo=tor.source.kernel.org; envelope-from=ljs@kernel.org; receiver=lists.ozlabs.org) Received: from tor.source.kernel.org (tor.source.kernel.org [IPv6:2600:3c04:e001:324:0:1991:8:25]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4hx7ML4Jb7z2yNj for ; Fri, 02 Oct 2026 22:27:10 +1000 (AEST) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 6F3FE60A8A; Fri, 2 Oct 2026 12:27:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C8FE1F000FF; Fri, 2 Oct 2026 12:26:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790944027; bh=hHcwGbw/dTLavCD1q0Wz915FUcvfzunoMb3D7u+JUi8=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=cxL+MpzC1cfSdjAOczoG1wPIbWTQrpCLMvzVBXSmnKiDFYDBMn64LTPj/OWtWuFXw gMS4it0MZsivPy8icpf5Socvb5mYV2Im4m2dtIO0izWysvPZaaVznKHHE8BUgxTm84 r9D0MJpBzqhVcI1wDRYzLV3kd3Y/HTsDcWwM/QeLKcJvTZvL+5LlcKmc0a0aAwrQ2U ZYFaZjVC0hCZ6nCAC8I0h5O90ago1k3NGUIsPkt6VWSJG/PggFTuZRQsBvT4/V6tEj +1USCOD4kbv5ptO7N71o+f+lwiUaQKKZEz6kENcKDRXDz8XMOg2VDIFttVx9pefZu/ Fg8q/hmZlpmxg== Date: Fri, 2 Oct 2026 13:26:38 +0100 From: "Lorenzo Stoakes (ARM)" To: Zi Yan Cc: Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Jann Horn , Pedro Falcato , David Hildenbrand , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jonathan Corbet , Greg Kroah-Hartman , Dennis Dalessandro , Jason Gunthorpe , Leon Romanovsky , Paul Moore , Stephen Smalley , Jaroslav Kysela , Takashi Iwai , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Kumar Kartikeya Dwivedi , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Kiryl Shutsemau , Doug Gilbert , "James E.J. Bottomley" , "Martin K. Petersen" , Jaya Kumar , Simona Vetter , Helge Deller , Sebastian Reichel , John Hubbard , Peter Xu , Masami Hiramatsu , Oleg Nesterov , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Rik van Riel , Harry Yoo , Juri Lelli , Vincent Guittot , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Arnd Bergmann , Muchun Song , Oscar Salvador , "Matthew Wilcox (Oracle)" , Jan Kara , Marc Zyngier , Oliver Upton , Catalin Marinas , Madhavan Srinivasan , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , "David S. Miller" , Andreas Larsson , Alexander Viro , Christian Brauner , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Youngjun Park , Johannes Weiner , Qi Zheng , Shakeel Butt , Axel Rasmussen , Yuanchu Xie , Wei Xu , Chengming Zhou , Michal Hocko , Miklos Szeredi , Xu Xin , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-usb@vger.kernel.org, linux-rdma@vger.kernel.org, selinux@vger.kernel.org, linux-sound@vger.kernel.org, bpf@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, fuse-devel@lists.linux.dev Subject: Re: [PATCH v3 23/40] mm/mlock: clear VMA_LOCKED_MASK over mmap callback Message-ID: References: <20260917-b4-mmap-prepare-vma-flag-sanify-v3-0-4583d8a23bca@kernel.org> <20260917-b4-mmap-prepare-vma-flag-sanify-v3-23-4583d8a23bca@kernel.org> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Oct 01, 2026 at 11:20:17AM -0400, Zi Yan wrote: > On Thu Sep 17, 2026 at 12:22 PM EDT, Lorenzo Stoakes (ARM) wrote: > > Currently there's a confusing mess around VMA_LOCKED_BIT and > > VMA_LOCKONFAULT_BIT. > > > > It is permitted for drivers to set any flags they like, with the VMA > > already possessing lock flags. > > > > This results in the absurd situation of a VMA possessing both > > VMA_SPECIAL_FLAGS and VMA_LOCKED_MASK flags, which is not permitted. > > > > This has resulted in mlock_vma_folio() having a very silly check for this > > scenario to work around it. > > > > There is no need for this - just clear the flags before invoking the hook > > and reinstate them afterwards if they are required. > > > > Nothing relies upon this being set during the mmap operation. > > > > mmap_prepare is unaffected by this so requires no fix. > > > > Signed-off-by: Lorenzo Stoakes (ARM) > > --- > > mm/internal.h | 9 +-------- > > mm/vma.c | 14 ++++++++++++++ > > 2 files changed, 15 insertions(+), 8 deletions(-) > > > > > > + /* If VMA flags still valid for locked mask, reinstate. */ > > + if (vma_supports_mlock(vma)) { > > + const vma_flags_t mask = > > + vma_flags_and_mask(&map->vma_flags, > > + VMA_LOCKED_MASK); > > + > > + vma_set_flags_mask(vma, mask); > > It took me a while to figure out vma_set_flags_mask() is an OR > operation. Yeah naming is hard :) Let me add a comment here though because it's kinda a bit unusual. > > > + } > > + > > map->vma_flags = vma->flags; > > > > return 0; > > Otherwise, LGTM. > > Reviewed-by: Zi Yan Thanks! > > > > -- > Best Regards, > Yan, Zi > -- Cheers, Lorenzo