From patchwork Mon Jun 14 09:05:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Price X-Patchwork-Id: 1491617 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4G3QkN0tjKz9sT6 for ; Mon, 14 Jun 2021 19:14:18 +1000 (AEST) Received: from localhost ([::1]:51110 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lsiff-0001Il-DS for incoming@patchwork.ozlabs.org; Mon, 14 Jun 2021 05:14:15 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50608) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lsiXS-0000wv-Kt for qemu-devel@nongnu.org; Mon, 14 Jun 2021 05:05:46 -0400 Received: from foss.arm.com ([217.140.110.172]:50862) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lsiXP-0005lB-6D for qemu-devel@nongnu.org; Mon, 14 Jun 2021 05:05:45 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C54F61FB; Mon, 14 Jun 2021 02:05:40 -0700 (PDT) Received: from e112269-lin.arm.com (autoplooker.cambridge.arm.com [10.1.194.57]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 062103F694; Mon, 14 Jun 2021 02:05:37 -0700 (PDT) From: Steven Price To: Catalin Marinas , Marc Zyngier , Will Deacon Subject: [PATCH v15 0/7] MTE support for KVM guest Date: Mon, 14 Jun 2021 10:05:18 +0100 Message-Id: <20210614090525.4338-1-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Received-SPF: pass client-ip=217.140.110.172; envelope-from=steven.price@arm.com; helo=foss.arm.com X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Peter Maydell , "Dr. David Alan Gilbert" , Andrew Jones , Haibo Xu , Suzuki K Poulose , qemu-devel@nongnu.org, Dave Martin , Juan Quintela , Richard Henderson , linux-kernel@vger.kernel.org, Steven Price , James Morse , Julien Thierry , Thomas Gleixner , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This series adds support for using the Arm Memory Tagging Extensions (MTE) in a KVM guest. I realise there are still open questions[1] around the performance of this series (the 'big lock', tag_sync_lock, introduced in the first patch). But there should be no impact on non-MTE workloads and until we get real MTE-enabled hardware it's hard to know whether there is a need for something more sophisticated or not. Peter Collingbourne's patch[3] to clear the tags at page allocation time should hide more of the impact for non-VM cases. So the remaining concern is around VM startup which could be effectively serialised through the lock. Changes since v14[2]: * Dropped "Handle MTE tags zeroing" patch in favour of Peter's similar patch[3] (now in arm64 tree). * Improved documentation following Catalin's review. [1]: https://lore.kernel.org/r/874ke7z3ng.wl-maz%40kernel.org [2]: https://lore.kernel.org/r/20210607110816.25762-1-steven.price@arm.com/ [3]: https://lore.kernel.org/r/20210602235230.3928842-4-pcc@google.com/ Steven Price (7): arm64: mte: Handle race when synchronising tags arm64: mte: Sync tags for pages where PTE is untagged KVM: arm64: Introduce MTE VM feature KVM: arm64: Save/restore MTE registers KVM: arm64: Expose KVM_ARM_CAP_MTE KVM: arm64: ioctl to fetch/store tags in a guest KVM: arm64: Document MTE capability and ioctl Documentation/virt/kvm/api.rst | 57 +++++++++++++++ arch/arm64/include/asm/kvm_arm.h | 3 +- arch/arm64/include/asm/kvm_emulate.h | 3 + arch/arm64/include/asm/kvm_host.h | 12 ++++ arch/arm64/include/asm/kvm_mte.h | 66 +++++++++++++++++ arch/arm64/include/asm/mte-def.h | 1 + arch/arm64/include/asm/mte.h | 8 ++- arch/arm64/include/asm/pgtable.h | 22 +++++- arch/arm64/include/asm/sysreg.h | 3 +- arch/arm64/include/uapi/asm/kvm.h | 11 +++ arch/arm64/kernel/asm-offsets.c | 2 + arch/arm64/kernel/mte.c | 54 ++++++++++++-- arch/arm64/kvm/arm.c | 16 +++++ arch/arm64/kvm/guest.c | 82 ++++++++++++++++++++++ arch/arm64/kvm/hyp/entry.S | 7 ++ arch/arm64/kvm/hyp/exception.c | 3 +- arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 21 ++++++ arch/arm64/kvm/mmu.c | 42 ++++++++++- arch/arm64/kvm/reset.c | 3 +- arch/arm64/kvm/sys_regs.c | 32 +++++++-- include/uapi/linux/kvm.h | 2 + 21 files changed, 429 insertions(+), 21 deletions(-) create mode 100644 arch/arm64/include/asm/kvm_mte.h