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 D4624C4167B for ; Tue, 5 Dec 2023 18:41:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ZVL0coEPgmJp1ASTXrhX3xI+ryFuEKHKq8sk19mEcQg=; b=PRp8NhMLT8IrAQ tayyjl0RXVUEfs+7AxdI7i881q8YDFRe8md2SxlF+XKurYQ24nakkGxNKk8W14lyW4qf5NTNJORs0 rHBPcoAQbwEZgNlKUbxkkZTP1QT4XoM/yePvVZedzBhuBWKBQ+2bSV+s04jpKN+CDkhqVR5DVWLMV uOQzTjywYIG1qkQ3maYLg0pJ6eigqkbWJpcEak4GzqGhfMKHulmkp5cjyhFe0kDoAAMKzx6qpnF4S mzoD9zKuFqeZ66G2v5Rqp8rxIL+OzYnYr5IjDAf+otJBIOaoxoILLDRxSYubUn7nRGE0n0dpJboqA B4hZLlVDR2EyMFae+avw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rAaLq-008B6E-2p; Tue, 05 Dec 2023 18:40:58 +0000 Received: from sin.source.kernel.org ([145.40.73.55]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rAaLn-008B5B-2M for linux-arm-kernel@lists.infradead.org; Tue, 05 Dec 2023 18:40:57 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 4BAFCCE1B28; Tue, 5 Dec 2023 18:40:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6FAB3C433C7; Tue, 5 Dec 2023 18:40:45 +0000 (UTC) Date: Tue, 5 Dec 2023 18:40:42 +0000 From: Catalin Marinas To: Marc Zyngier Cc: Jason Gunthorpe , ankita@nvidia.com, Shameerali Kolothum Thodi , oliver.upton@linux.dev, suzuki.poulose@arm.com, yuzenghui@huawei.com, will@kernel.org, ardb@kernel.org, akpm@linux-foundation.org, gshan@redhat.com, aniketa@nvidia.com, cjia@nvidia.com, kwankhede@nvidia.com, targupta@nvidia.com, vsethi@nvidia.com, acurrid@nvidia.com, apopple@nvidia.com, jhubbard@nvidia.com, danw@nvidia.com, mochs@nvidia.com, kvmarm@lists.linux.dev, kvm@vger.kernel.org, lpieralisi@kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 1/1] KVM: arm64: allow the VM to select DEVICE_* and NORMAL_NC for IO memory Message-ID: References: <20231205033015.10044-1-ankita@nvidia.com> <86fs0hatt3.wl-maz@kernel.org> <20231205130517.GD2692119@nvidia.com> <20231205164318.GG2692119@nvidia.com> <86bkb4bn2v.wl-maz@kernel.org> <86a5qobkt8.wl-maz@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <86a5qobkt8.wl-maz@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231205_104055_999376_0CDFA08D X-CRM114-Status: GOOD ( 14.66 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Dec 05, 2023 at 05:50:27PM +0000, Marc Zyngier wrote: > On Tue, 05 Dec 2023 17:33:01 +0000, > Catalin Marinas wrote: > > Ideally we should do this for vfio only but we don't have an easy > > way to convey this to KVM. > > But if we want to limit this to PCIe, we'll have to find out. The > initial proposal (a long while ago) had a flag conveying some > information, and I'd definitely feel more confident having something > like that. We can add a VM_PCI_IO in the high vma flags to be set by vfio_pci_core_mmap(), though it limits it to 64-bit architectures. KVM knows this is PCI and relaxes things a bit. It's not generic though if we need this later for something else. A question for Lorenzo: do these BARs appear in iomem_resource? We could search that up instead of a flag, something like the page_is_ram() helper. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel