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 X-Spam-Level: X-Spam-Status: No, score=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D4B56C48BE6 for ; Mon, 14 Jun 2021 09:05:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A555D611CA for ; Mon, 14 Jun 2021 09:05:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232663AbhFNJHo (ORCPT ); Mon, 14 Jun 2021 05:07:44 -0400 Received: from foss.arm.com ([217.140.110.172]:58204 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232602AbhFNJHn (ORCPT ); Mon, 14 Jun 2021 05:07:43 -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 Cc: Steven Price , James Morse , Julien Thierry , Suzuki K Poulose , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Dave Martin , Mark Rutland , Thomas Gleixner , qemu-devel@nongnu.org, Juan Quintela , "Dr. David Alan Gilbert" , Richard Henderson , Peter Maydell , Haibo Xu , Andrew Jones 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 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 -- 2.20.1