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 13B3ACA9EDD for ; Mon, 12 Oct 2026 15:56:23 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4j3MX629PZz3bV5; Tue, 13 Oct 2026 02:56:22 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; arc=none smtp.remote-ip="2600:3c0a:e001:78e:0:1991:8:25" ARC-Seal: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1791820582; cv=none; b=jLS8R4fsZu3quH4GAbW1L8OVvZMUkdeE5HCJiuTRIaTCecOewnryMKrLXd8SMOk+UwBviU9tw1PXq36bqGAdh0AkwlCzVCZtIz9isN9HraxLZKGUC0H3OeqSsIQPEEIfNrzIvO2OitP6sFtOP6kdh1wylJ76e1+bMgYnRdTG1MGeEcgHNqil8atYgPOf7v9Owtr6AxDjIhh3JNH19s5FSWIf5Oy3i+ye1J1NSPsPxIW5jsh0bOLC7KiHd/v80SMswNDzNGLnvjppuHS+fc/BZlaT3xggSVPb4y2GodayvuCmVkx99GuRrRQlpFwKwOeQz3adKUghYoa9TdQ9JeDO+A== ARC-Message-Signature: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1791820582; c=relaxed/relaxed; bh=rFbms1O2vgiDwDr5XNy7hfOQCE1GiDGN4QD7DcgiMNU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=TbiXYdwiuZ233Chm5xjGWicSzSI4m8+jXPTx5zuVXpiIxqXYGwIGQgL92lar9qYMwL4Z1sGafCapggz1HE/1bUWptWUhk0jwzWe6PdOeBC0KL3BmOE20zAwnZriV+venrmsDE6AqjsG3i9vdi6/rpWVxsbF8MDIlmMb6GcPkSgmsptEGWq1E4e9H9iVilH/ONOx09WpPlUC1m8zsb2WazPLyDrREyk0LnHS1OVtyR/X/GKYdSlIvHe6vo3gei+8uaEHOF61swUOvertSIjSBO4CcFu/hzbilxZVVFy0MoL4M8cUq5EcmE4aNFDBSKgwXadYMq+RfBaK2x7snkR/Xpg== 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=lcCuIdrm; dkim-atps=neutral; spf=pass (client-ip=2600:3c0a:e001:78e:0:1991:8:25; helo=sea.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=lcCuIdrm; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=2600:3c0a:e001:78e:0:1991:8:25; helo=sea.source.kernel.org; envelope-from=ljs@kernel.org; receiver=lists.ozlabs.org) Received: from sea.source.kernel.org (sea.source.kernel.org [IPv6:2600:3c0a:e001:78e:0:1991:8:25]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4j3MX51NgTz3bNr for ; Tue, 13 Oct 2026 02:56:21 +1100 (AEDT) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id EEBE4404DC; Mon, 12 Oct 2026 15:56:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CFCE21F0089B; Mon, 12 Oct 2026 15:55:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791820577; bh=rFbms1O2vgiDwDr5XNy7hfOQCE1GiDGN4QD7DcgiMNU=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=lcCuIdrmMQTUiPwLl5e5Z+CrC201P9TaW7VntAlAQ0wuTIeWArybWpskzP1Cw5dV6 ylJBpTsnaVkD11Tx3RuJLQfK/a8MthDkbqh/N2Qo+NL+mbeJ3F+l2nHLzRgl2fwWrH B2VMH6xZ4mSRm44O1aVrnpq4KXOYj1KBkqJhj4Zhsip2ZHKhYDPIEZ9S25S3KUpDrh 0/izKAMAcRM9eWvuTZfpYIL58pwYVIybump371ArBjzbMrNsvpmDwuL9EdnDMlpqUp x6n3EvLO70LPCbwLxz+x7mIQrXQvvZz8TgmnlRpMjxmuB8UzGsynS78NvOMo7KMLyg CQyvIZ4fN7eXw== Date: Mon, 12 Oct 2026 16:55:44 +0100 From: "Lorenzo Stoakes (ARM)" To: "David Hildenbrand (Arm)" Cc: Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Jann Horn , Pedro Falcato , 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 , Zi Yan , 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" , 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, Ihor Solodrai , Bert Karwatzki , Emil Tsalapatis Subject: Re: [PATCH v5 13/38] bpf: arena: mark arena_map_mmap() mappings VM_MIXEDMAP Message-ID: References: <20261009-b4-mmap-prepare-vma-flag-sanify-v5-0-923b70125b1e@kernel.org> <20261009-b4-mmap-prepare-vma-flag-sanify-v5-13-923b70125b1e@kernel.org> <5b8ef0ce-7429-4d74-b4da-a0561c59b1e2@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: <5b8ef0ce-7429-4d74-b4da-a0561c59b1e2@kernel.org> On Mon, Oct 12, 2026 at 05:08:09PM +0200, David Hildenbrand (Arm) wrote: > On 10/9/26 20:04, Lorenzo Stoakes (ARM) wrote: > > diff --git a/kernel/bpf/arena.c b/kernel/bpf/arena.c > > index 7b6847200b43..b69fe5e34339 100644 > > --- a/kernel/bpf/arena.c > > +++ b/kernel/bpf/arena.c > > @@ -620,8 +620,9 @@ static int arena_map_mmap(struct bpf_map *map, struct vm_area_struct *vma) > > * clears VM_MAYEXEC. Set VM_DONTEXPAND to avoid potential change > > * of user_vm_start. Set VM_DONTCOPY to prevent arena VMA from > > * being copied into the child process on fork. > > + * This is a kernel page so set VM_MIXEDMAP. > > */ > > - vm_flags_set(vma, VM_DONTEXPAND | VM_DONTCOPY); > > + vm_flags_set(vma, VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTCOPY); > > vma->vm_ops = &arena_vm_ops; > > return 0; > > } > > > > Historically, VM_MIXEDMAP really just means: can contain refcounted and > non-refcounted things. Everything with a struct page is refcounted. > > I think we are now changing the semantics to mean "maps kernel pages". I think Yes. It was sort of implicit before given insert_page() etc. but still really meaning that it _might_ be both. > this is fine, but we really have to update the documentation (and possibly > rename this thing to something more expressive?) Yeah I completely agree. I will rename it, but I think that's best for 7.5 obviously! :) > > Acked-by: David Hildenbrand (Arm) Thanks! -- Cheers, Lorenzo