From patchwork Fri Nov 19 13:47:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Peng X-Patchwork-Id: 12628921 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77BECC433F5 for ; Fri, 19 Nov 2021 13:50:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 62E5761247 for ; Fri, 19 Nov 2021 13:50:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235802AbhKSNxY (ORCPT ); Fri, 19 Nov 2021 08:53:24 -0500 Received: from mga07.intel.com ([134.134.136.100]:42184 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235799AbhKSNxX (ORCPT ); Fri, 19 Nov 2021 08:53:23 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10172"; a="297831271" X-IronPort-AV: E=Sophos;i="5.87,247,1631602800"; d="scan'208";a="297831271" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Nov 2021 05:50:21 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,247,1631602800"; d="scan'208";a="507905274" Received: from chaop.bj.intel.com ([10.240.192.101]) by orsmga008.jf.intel.com with ESMTP; 19 Nov 2021 05:50:13 -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: [RFC v2 PATCH 13/13] KVM: Enable memfd based page invalidation/fallocate Date: Fri, 19 Nov 2021 21:47:39 +0800 Message-Id: <20211119134739.20218-14-chao.p.peng@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211119134739.20218-1-chao.p.peng@linux.intel.com> References: <20211119134739.20218-1-chao.p.peng@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Since the memory backing store does not get notified when VM is destroyed so need check if VM is still live in these callbacks. Signed-off-by: Yu Zhang Signed-off-by: Chao Peng --- virt/kvm/memfd.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/virt/kvm/memfd.c b/virt/kvm/memfd.c index bd930dcb455f..bcfdc685ce22 100644 --- a/virt/kvm/memfd.c +++ b/virt/kvm/memfd.c @@ -12,16 +12,38 @@ #include const static struct guest_mem_ops *memfd_ops; +static bool vm_is_dead(struct kvm *vm) +{ + struct kvm *kvm; + + list_for_each_entry(kvm, &vm_list, vm_list) { + if (kvm == vm) + return false; + } + + return true; +} + static void memfd_invalidate_page_range(struct inode *inode, void *owner, pgoff_t start, pgoff_t end) { //!!!We can get here after the owner no longer exists + if (vm_is_dead(owner)) + return; + + kvm_memfd_invalidate_range(owner, inode, start >> PAGE_SHIFT, + end >> PAGE_SHIFT); } static void memfd_fallocate(struct inode *inode, void *owner, pgoff_t start, pgoff_t end) { //!!!We can get here after the owner no longer exists + if (vm_is_dead(owner)) + return; + + kvm_memfd_fallocate_range(owner, inode, start >> PAGE_SHIFT, + end >> PAGE_SHIFT); } static const struct guest_ops memfd_notifier = {