From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 49AEF4A8FC2; Mon, 12 Oct 2026 15:56:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791820579; cv=none; b=XMlr4rjASxVMPlaek7kHdUETpFPm2InPWAGJSDWZJjoCgannqLrAUO66dVllJOFOwBaG1NpqFLWhDYIxmF1+5aYdS4dGxkrGh1mZXXG5UdgaSqt//VDblKS4+6NhFfKU930RFiGo6Q6pntQmhI/jbl3uUfN3XKk+9DOjOgMXLsA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791820579; c=relaxed/simple; bh=Msp9ikSwVnULK/6DWYXJFuVVmnxjiRI6tilrQPvf9sc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=lEyy1SVc25ByWpuaeECuUF+HlptxiXy4lCjQl/1kVxqgv4MVTom9+kMwwetFq0UblXm3GmaH64oPn1kxosHdSyEMBMW8SoF1dybx8m3ePtqFTcqtDmjnfKODC/mC77Rm9d3qFpZmHtbwmIW0yWZe6dL6FDqhgwdZ+jcb77DB3rE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lcCuIdrm; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="lcCuIdrm" 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> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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