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 4D2B5E7717F for ; Tue, 10 Dec 2024 14:46:33 +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=pO8jq8K05ziX1kKttCa3ywuA95Peb+QVwhVURYTEVAk=; b=eACl0BxaUS462YhmDIoT43STjq UOkVj7/7w3I3g2Hwnh+lsjTfi4SYqSqDvs8loGv8n3E81FbARDLOVanXw/A3Z0y9JRfKB0PwxVaq8 /AVUlHLMUY71mISVmM9XK+UOVGK9ff4ZGOyhBIYfWQHlEOLkj5J9zQmTR3RWRRjBr4OOzP0TwoqTZ QpVz3mIwAcavxOOZYXS0Ab5vqq2ZpsWLhLRtYzSG2JXl+EZsp+4woIP1wOmBkxgAlXUwTclF8uyAI Un/E9BIbpzEJ+8sPVoOHWccsGkuUBXDHALjEvdPGFjTcKqrM/7MPanXApzYkL7I+52ansK5F/7YTj ghe2ku5Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tL1VD-0000000Bpt0-2Zqi; Tue, 10 Dec 2024 14:46:19 +0000 Received: from nyc.source.kernel.org ([147.75.193.91]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tL1U8-0000000BpfG-03jW for linux-arm-kernel@lists.infradead.org; Tue, 10 Dec 2024 14:45:13 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 7B913A41908; Tue, 10 Dec 2024 14:43:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B804BC4CED6; Tue, 10 Dec 2024 14:45:03 +0000 (UTC) Date: Tue, 10 Dec 2024 14:45:01 +0000 From: Catalin Marinas To: Jason Gunthorpe Cc: Will Deacon , ankita@nvidia.com, maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, ryan.roberts@arm.com, shahuang@redhat.com, lpieralisi@kernel.org, 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, zhiw@nvidia.com, mochs@nvidia.com, udhoke@nvidia.com, dnigam@nvidia.com, alex.williamson@redhat.com, sebastianene@google.com, coltonlewis@google.com, kevin.tian@intel.com, yi.l.liu@intel.com, ardb@kernel.org, akpm@linux-foundation.org, gshan@redhat.com, linux-mm@kvack.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 0/1] KVM: arm64: Map GPU memory with no struct pages Message-ID: References: <20241118131958.4609-1-ankita@nvidia.com> <20241210140739.GC15607@willie-the-truck> <20241210141806.GI2347147@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241210141806.GI2347147@nvidia.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241210_064512_117394_58A89883 X-CRM114-Status: GOOD ( 18.48 ) 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 Tue, Dec 10, 2024 at 10:18:06AM -0400, Jason Gunthorpe wrote: > On Tue, Dec 10, 2024 at 02:07:40PM +0000, Will Deacon wrote: > > On Mon, Nov 18, 2024 at 01:19:57PM +0000, ankita@nvidia.com wrote: > > > The changes are heavily influenced by the insightful discussions between > > > Catalin Marinas and Jason Gunthorpe [1] on v1. Many thanks for their > > > valuable suggestions. > > > > > > Link: https://lore.kernel.org/lkml/20230907181459.18145-2-ankita@nvidia.com [1] > > > > That's a different series, no? It got merged at v9: > > I was confused by this too. v1 of that series included this patch, as > that series went along it became focused only on enabling WC > (Normal-NC) in a VM for device MMIO and this patch for device cachable > memory was dropped off. > > There are two related things: > 1) Device MMIO memory should be able to be Normal-NC in a VM. Already > merged > 2) Device Cachable memory (ie CXL and pre-CXL coherently attached > memory) should be Normal Cachable in a VM, even if it doesn't have > struct page/etc. (this patch) > > IIRC this part was dropped off because of the MTE complexity that > Catalin raised. Indeed, we only merged the Normal NC part at the time. I asked Ankit to drop the cacheable attributes and only focus on getting the other part merged. -- Catalin