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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 359EAC83F1B for ; Mon, 14 Jul 2025 10:14:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=xIA6a+smY3CSNk281uBRTI98m0jey8d7+OFhMF9gjAw=; b=1bXL9K2+jTElwhE1om2S7f7pXh vmDhGqz00JjrnZXQBRmsUmLIV26LwVFRoS9sKMVhFmwOfXNBDET9LLoFyQnqextDZzkHBTd6KTGIq LjfLTC5T8jffzYyM/AhVo7wVc/rw/JraOANvEeksrZ+bwQ1mxG9IEBTP9sTxp09YHBb68gqzA7tDv Kuh/BhHcwS8tAq9xrHRKI7k308hOtyuux7MUSPO/oibMs+zUwRmjIugRomGib2aGgPCSQjmUCe/5V ycPK5lOGzAO7heROfP8ql8QFEmTUjYEwbk4zaxn47vbs+NjJdelFEXNPR1+8YNQWhRGkJRhiFqj3+ gnU3wnxA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1ubGCr-00000001tNW-3qEr; Mon, 14 Jul 2025 10:14:45 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1ubFx7-00000001r6r-3vtN for linux-arm-kernel@lists.infradead.org; Mon, 14 Jul 2025 09:58:31 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 5A5484645D; Mon, 14 Jul 2025 09:58:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E4E74C4CEED; Mon, 14 Jul 2025 09:58:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752487109; bh=6QNF2IYiYqPBBrAD5MOXPmWbh+lwfMKKPRRBenmPnKQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Ums9ayJN5n832EVbsV69MWCMFHIkAtW87SJM8xhoU99WdXpmOoi01pg9sXFG35BQS aemOss8YmGLTKcVZME8JuPe0FdkYnSVBD1HdZecjl2w2e7vKAKutLFr3E7F3bicd5+ 9avX8BMP5vaoKP+RN35dD7u12iVolLIZDw4tpncBqTA7E/v7xxgFzTq7yaqVan8JTP aiU4E6arkoWr1hRxCAVVg+HPdswYptXzXyA6cSqLZZDPSSszrgttAO5Y1iHpF4pQHQ UN7wUd2CHCpbhrA9HFwRNP9EDFwfGeKyhjzoB2IzipZUDUkeBEAUBDNmPkrtlaguFS Jjw/Am5jCSaZA== Date: Mon, 14 Jul 2025 10:58:23 +0100 From: Will Deacon To: DaeRo Lee Cc: alexandru.elisei@arm.com, james.morse@arm.com, kernel-team@android.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, maz@kernel.org, oliver.upton@linux.dev, qperret@google.com, sebastianene@google.com, sudeep.holla@arm.com, suzuki.poulose@arm.com, tabba@google.com Subject: Re: [PATCH v3 08/10] KVM: arm64: Handle FFA_MEM_LEND calls from the host Message-ID: References: <20250714021400.631762-1-skseofh@naver.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250714021400.631762-1-skseofh@naver.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250714_025829_996962_0E767A9C X-CRM114-Status: UNSURE ( 8.35 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jul 14, 2025 at 11:14:00AM +0900, DaeRo Lee wrote: > Is it pKVM's policy to not manage Non-secure memory using FF-A, while the FF-A > specification supports memory management between Host/Guest within Non-secure > hypervisors? > > Then, how does someone lend memory to a Guest from the Host/Guest via FF-A? Can > pKVM prevent this? Or should Host/Guest developers use it with caution? Perhaps you could read the code and find out. Will