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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7474BC677F1 for ; Fri, 20 Jan 2023 04:28:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230032AbjATE2r (ORCPT ); Thu, 19 Jan 2023 23:28:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229797AbjATE2b (ORCPT ); Thu, 19 Jan 2023 23:28:31 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AEDEDB1ED3; Thu, 19 Jan 2023 20:28:27 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 279F8B82698; Thu, 19 Jan 2023 17:24:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C0EE7C433EF; Thu, 19 Jan 2023 17:24:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1674149068; bh=esmAuiMb4cE5hZfqa2pdZ4JKU4zWFBBvjoAoXwc+zAk=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=FItgwmM67QScUUENZ8Zwtagr5mIdG5cEHxPFfSNuC1jM6dBrsQGhnCtdKL1v4Yf0w dW3PN2nS8nWYwK6BvAjRYCRs1jNPqcxP6UwIOvTzzQ9T/wZ6VcEzgDHqur2z3W0vff Q1U6HgQ7VMeTq9MX32okWCpOlh8xJ8QfczraVmhyB125dZQ7bsUFjHD48Lr2RB1Xwn dCD05u76MAQiAcbWsup1KSQa2MZ/UMnuWZVUxW8VbUZw7v99qBSmYLqsbt+GBlaRNB uIlEinXfjpAehqjV461mc7XifGdWsWw6VTkhkWgCHrf79SoBq2+sYdBD1CdMnGEwy+ 8vQzGzULTP5uQ== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1pIYeI-003A4j-5l; Thu, 19 Jan 2023 17:24:26 +0000 Date: Thu, 19 Jan 2023 17:24:25 +0000 Message-ID: <86tu0mmo8m.wl-maz@kernel.org> From: Marc Zyngier To: David Matlack Cc: Paolo Bonzini , James Morse , Alexandru Elisei , Suzuki K Poulose , Oliver Upton , Huacai Chen , Aleksandar Markovic , Anup Patel , Atish Patra , Paul Walmsley , Palmer Dabbelt , Albert Ou , Sean Christopherson , Andrew Morton , Anshuman Khandual , Nadav Amit , "Matthew Wilcox (Oracle)" , Vlastimil Babka , "Liam R. Howlett" , Suren Baghdasaryan , Peter Xu , xu xin , Arnd Bergmann , Yu Zhao , Colin Cross , Hugh Dickins , Ben Gardon , Mingwei Zhang , Krish Sadhukhan , Ricardo Koller , Jing Zhang , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvmarm@lists.cs.columbia.edu, linux-mips@vger.kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, Alexandre Ghiti , Raghavendra Rao Ananta Subject: Re: [RFC PATCH 00/37] KVM: Refactor the KVM/x86 TDP MMU into common code In-Reply-To: References: <20221208193857.4090582-1-dmatlack@google.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/28.2 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: dmatlack@google.com, pbonzini@redhat.com, james.morse@arm.com, alexandru.elisei@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, chenhuacai@kernel.org, aleksandar.qemu.devel@gmail.com, anup@brainfault.org, atishp@atishpatra.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, seanjc@google.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, namit@vmware.com, willy@infradead.org, vbabka@suse.cz, Liam.Howlett@oracle.com, surenb@google.com, peterx@redhat.com, cgel.zte@gmail.com, arnd@arndb.de, yuzhao@google.com, ccross@google.com, hughd@google.com, bgardon@google.com, mizhang@google.com, krish.sadhukhan@oracle.com, ricarkol@google.com, jingzhangos@google.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvmarm@lists.cs.columbia.edu, linux-mips@vger.kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, alexghiti@rivosinc.com, rananta@google.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Thu, 19 Jan 2023 17:14:34 +0000, David Matlack wrote: > > On Thu, Dec 08, 2022 at 11:38:20AM -0800, David Matlack wrote: > > > > Hello, > > > > This series refactors the KVM/x86 "TDP MMU" into common code. This is > > the first step toward sharing TDP (aka Stage-2) page table management > > code across architectures that support KVM. > > Thank you everyone for the feedback on this RFC. I have a couple of > updates to share and a question at the end. > > First, Alexandre Ghiti from Rivos is going to work on the RISC-V port. > I'd like to target RISC-V first, since it has significantly lower risk > and complexity than e.g. ARM (which has pKVM, stage-1 walkers, and > [soon] nested virtualization to deal with). And (joy, happiness), the upcoming 128bit page table support[1]. M. [1] https://developer.arm.com/documentation/ddi0601/2022-12/AArch64-Registers/TTBR0-EL1--Translation-Table-Base-Register-0--EL1-?lang=en -- Without deviation from the norm, progress is not possible.