From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793253202; b=0RVwzxms+/b8/wC8LyjLlWpF7wFwA7WvZCrQZdJqeF7CAzDRxIuVXS7P/E9xROWLXvhL 7Jin0EtMIGU5VQ35P8IPiUqs0DhQB3+XRlYjUhRO+gMl2f0D+Lralw+3dku7+t+S201NP 4UpQguSZV0+6TfYuauF4hdOOC7PWusZySLkjzS3gOk1vjjxKkHjHTKs5YE060rFzzYT8W SzZZIjV0Nitb2bzJlhuBSw15kPLVNZGC+1PYubk7z6aCOVUUgcXVycVJU5utDC3Nq9FEw T23F07ORCMDNpTIV1J914ysXC0L0psodEoeyN+1K7shnh+FGvnseJxfffz/hPg3euvA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793253202; h=Received:DKIM-Signature:X-Mailer:From:To:Cc:Subject:In-Reply-To: References:Date:Message-ID:MIME-Version:Content-Type; bh=uj4lN0l73poxUX+FmN14sN+KhrHh46mzInZ+w/lSNOA=; b=SRZYU5uvlW28be0OVZrmfYdcqrqYYSqa0W7QjGGDq0txgnJ1oAzzGCqFEBTIM9VpupRV 68lC9SH8hnNK8qcVvxCfh6Ijx30jLGqNcTOOZCFKuTpmCpuJx9itUT95OPRRmyUDXgObB oDa+ZMsqOf+e017nH4CezbWSsh5EJuBgzzfEmoAiANQtki9w2FEusZMGwSqxDky93+QAX IGLRWiOllhBWf9sGQXHrJQUjeskEPO2rXA0Xkc0QCbiQcLYleNlHr2xKh/Kb/i+Om0ccN fxmEd7vg37YaWzCoQOJV0zzao8U1Y748cNa2OMt732eu/QtUBp5+LlPAdgx/eG+DA6A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=f4UzML0E; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F394606A31A; Thu, 29 Oct 2026 05:53:22 +0000 (UTC) Authentication-Results: smtp.subspace.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=f4UzML0E Received: by smtp.kernel.org (Postfix) with ESMTPSA id BE01B1F01829; Thu, 29 Oct 2026 05:53:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793253202; bh=uj4lN0l73poxUX+FmN14sN+KhrHh46mzInZ+w/lSNOA=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=f4UzML0ErVF+LAoa1vMt9mZJRViUBFoCp4qAhid0FJ375+eCUkscN3nrQ+SxHaHIc WuoEBI1IRIIMzX5ZITRFCo+KBtNHOYAKcxiWsH2bHbiIUUSzfWMG4Agl65uvlKgCUE 4GkmPhPZ3f1jP1zxDZKdwb0zCtl8JXPgilBKrUWyIBu+ShSYeJ2VMD1zYSKTZGZXBB pxp58kmWohBUeeSTsbk4tvKWW3S8UqZj/30T4z8+6DjJsgRm8l2O4LbUYA00UHN7yZ 8gmiRO3pPcVPpm9q+uwqGjTkcbyU3tstmRuUbpdDyudJr9ey2cv7XmwTAY/POea5pe +0f9fSCBfw89g== X-Mailer: emacs 31.1 (via feedmail 11-beta-1 I) From: Aneesh Kumar K.V To: Ackerley Tng via B4 Relay , Alex Williamson , Alexander Graf , Alexander Viro , Alexey Kardashevskiy , Andrew Morton , Ashish Kalra , Baolin Wang , Baolu Lu , Bill Wendling , Borislav Petkov , Catalin Marinas , Christian Brauner , Christian =?utf-8?Q?K=C3=B6nig?= , Connor Williamson , Dave Hansen , Dave Jiang , David Hildenbrand , David Rientjes , David Woodhouse , Erdem Aktas , Frank van der Linden , Fred Griffoul , Fred Griffoul , Gregory Price , "H. Peter Anvin" , Hugh Dickins , Ingo Molnar , Jacob Pan , James Houghton , Jan Kara , Jason Gunthorpe , Jianxiong Gao , Joerg Roedel , Joey Gouly , John Starks , Jonathan Corbet , Justin Stitt , Kevin Tian , Lorenzo Stoakes , Marc Zyngier , Michael Roth , Mike Rapoport , Nathan Chancellor , Nick Desaulniers , Nicolin Chen , Oliver Upton , Paolo Bonzini , Pratyush Yadav , Randy Dunlap , Robin Murphy , Samiullah Khawaja , Sean Christopherson , Shuah Khan , Steffen Eiden , Steven Price , Suzuki K Poulose , Tarun Sahu , Thomas Gleixner , Tom Lendacky , Tycho Andersen , Vishal Annapurve , Vlastimil Babka , Will Deacon , Xu Yilun , Yan Zhao , Zenghui Yu , x86@kernel.org, Shuah Khan , Fuad Tabba Cc: kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, llvm@lists.linux.dev, Ackerley Tng Subject: Re: [PATCH RFC v2 00/50] guest_memfd alternative providers In-Reply-To: <20261022-gmem-alternative-providers-v2-0-5dd1dc6c660a@google.com> References: <20261022-gmem-alternative-providers-v2-0-5dd1dc6c660a@google.com> Date: Thu, 29 Oct 2026 11:22:59 +0530 Message-ID: X-Mailing-List: kvm@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain Ackerley Tng via B4 Relay writes: > Here's RFC v2 of guest_memfd alternative providers, continuing from "Allow > guest_memfd to be created using a resource (pool) fd", which I'm considering > RFC v1. > [ ... 138 lines skipped ... ] > > Aneesh, thanks for your series [4], I haven't got a chance to look at it yet. I > will before I continue this prototype for IOMMU. I want to get feedback on this > part first. > I am looking at rebasing my series on top of this one. One detail we need to finalize is memory access through resource_fd. For a VFIO fd, I believe we want to continue allowing access through that fd. This means allowing read/write/mmap/ioctl, with the VFIO subsystem accessors checking whether the memory is host-accessible before accessing private PFNs [1]. My series denies mmap through the guest_memfd fd. https://lore.kernel.org/all/yq5a1p9qxmqg.fsf@kernel.org -aneesh