From patchwork Thu Dec 23 12:30:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Peng X-Patchwork-Id: 12698249 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 A0957C433EF for ; Thu, 23 Dec 2021 12:32:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348459AbhLWMcl (ORCPT ); Thu, 23 Dec 2021 07:32:41 -0500 Received: from mga01.intel.com ([192.55.52.88]:20726 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243706AbhLWMck (ORCPT ); Thu, 23 Dec 2021 07:32:40 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1640262760; x=1671798760; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=BEfM/tVOpaAZqZG+iExZFe2tWlUrZuoAMwYVM4OH/aE=; b=P6RAsWxWRgTlJZDqbR/hQQb+kVP+N3mnriYc8XCtpjSwre2+/ykhG1AR HXUM3fWhrCSjZQvTmhaZg57m4WYOUHGk7LlWcIQNkPs8dt6UGtQg07qT5 4k0xhv0Z47jo26v+zrz+oHi/Wpk6Lz00VW3vj9m/ZMnxktsJP5qGth/pp 20FexrlsE91wjX4eqM1Z10mG8ZHKBKztAWDXk9gz7NhaawUmXzc12lz1w uWg8EZQ3xgjdG44HnPfs6uJqhSL8VBvFJpH8F+GV+jGOtT8hKB5y+SdFy IQje7VIQa2iJzmX1c+KViPsEPemou6BCR9BhcP9J6cEumj7zY/GeHrN48 A==; X-IronPort-AV: E=McAfee;i="6200,9189,10206"; a="265026980" X-IronPort-AV: E=Sophos;i="5.88,229,1635231600"; d="scan'208";a="265026980" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Dec 2021 04:32:39 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,229,1635231600"; d="scan'208";a="522079039" Received: from chaop.bj.intel.com ([10.240.192.101]) by orsmga008.jf.intel.com with ESMTP; 23 Dec 2021 04:32:31 -0800 From: Chao Peng To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, qemu-devel@nongnu.org Cc: Paolo Bonzini , Jonathan Corbet , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H . Peter Anvin" , Hugh Dickins , Jeff Layton , "J . Bruce Fields" , Andrew Morton , Yu Zhang , Chao Peng , "Kirill A . Shutemov" , luto@kernel.org, john.ji@intel.com, susie.li@intel.com, jun.nakajima@intel.com, dave.hansen@intel.com, ak@linux.intel.com, david@redhat.com Subject: [PATCH v3 kvm/queue 13/16] KVM: Add KVM_EXIT_MEMORY_ERROR exit Date: Thu, 23 Dec 2021 20:30:08 +0800 Message-Id: <20211223123011.41044-14-chao.p.peng@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211223123011.41044-1-chao.p.peng@linux.intel.com> References: <20211223123011.41044-1-chao.p.peng@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This new exit allows user space to handle memory-related errors. Currently it supports two types (KVM_EXIT_MEM_MAP_SHARED/PRIVATE) of errors which are used for shared memory <-> private memory conversion in memory encryption usage. After private memory is enabled, there are two places in KVM that can exit to userspace to trigger private <-> shared conversion: - explicit conversion: happens when guest explicitly calls into KVM to map a range (as private or shared), KVM then exits to userspace to do the map/unmap operations. - implicit conversion: happens in KVM page fault handler. * if the fault is due to a private memory access then causes a userspace exit for a shared->private conversion request when the page has not been allocated in the private memory backend. * If the fault is due to a shared memory access then causes a userspace exit for a private->shared conversion request when the page has already been allocated in the private memory backend. Signed-off-by: Yu Zhang Signed-off-by: Chao Peng --- include/uapi/linux/kvm.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 41434322fa23..d68db3b2eeec 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -243,6 +243,18 @@ struct kvm_xen_exit { } u; }; +struct kvm_memory_exit { +#define KVM_EXIT_MEM_MAP_SHARED 1 +#define KVM_EXIT_MEM_MAP_PRIVATE 2 + __u32 type; + union { + struct { + __u64 gpa; + __u64 size; + } map; + } u; +}; + #define KVM_S390_GET_SKEYS_NONE 1 #define KVM_S390_SKEYS_MAX 1048576 @@ -282,6 +294,7 @@ struct kvm_xen_exit { #define KVM_EXIT_X86_BUS_LOCK 33 #define KVM_EXIT_XEN 34 #define KVM_EXIT_RISCV_SBI 35 +#define KVM_EXIT_MEMORY_ERROR 36 /* For KVM_EXIT_INTERNAL_ERROR */ /* Emulate instruction failed. */ @@ -499,6 +512,8 @@ struct kvm_run { unsigned long args[6]; unsigned long ret[2]; } riscv_sbi; + /* KVM_EXIT_MEMORY_ERROR */ + struct kvm_memory_exit mem; /* Fix the size of the union. */ char padding[256]; };