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: 12628945 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 5903CC433F5 for ; Fri, 19 Nov 2021 13:55:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F31C661547 for ; Fri, 19 Nov 2021 13:55:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org F31C661547 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id D428C6B0092; Fri, 19 Nov 2021 08:50:33 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id CF1C16B0093; Fri, 19 Nov 2021 08:50:33 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BBA366B0095; Fri, 19 Nov 2021 08:50:33 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0065.hostedemail.com [216.40.44.65]) by kanga.kvack.org (Postfix) with ESMTP id AD1606B0092 for ; Fri, 19 Nov 2021 08:50:33 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 5C5DB184B56CE for ; Fri, 19 Nov 2021 13:50:23 +0000 (UTC) X-FDA: 78825814536.05.6A1D538 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf23.hostedemail.com (Postfix) with ESMTP id 60EF99000383 for ; Fri, 19 Nov 2021 13:50:20 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10172"; a="297831270" X-IronPort-AV: E=Sophos;i="5.87,247,1631602800"; d="scan'208";a="297831270" 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> X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 60EF99000383 Authentication-Results: imf23.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf23.hostedemail.com: domain of chao.p.peng@linux.intel.com has no SPF policy when checking 134.134.136.100) smtp.mailfrom=chao.p.peng@linux.intel.com X-Stat-Signature: 1ptukx1ckup5jt87apsme7zqiosqf95i X-HE-Tag: 1637329820-647231 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 = {