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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 DCDCDC2D0D1 for ; Wed, 18 Dec 2019 21:56:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BA39321D7D for ; Wed, 18 Dec 2019 21:56:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727400AbfLRV4L (ORCPT ); Wed, 18 Dec 2019 16:56:11 -0500 Received: from mga04.intel.com ([192.55.52.120]:16973 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727344AbfLRV4E (ORCPT ); Wed, 18 Dec 2019 16:56:04 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 18 Dec 2019 13:55:52 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,330,1571727600"; d="scan'208";a="222108195" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.202]) by fmsmga001.fm.intel.com with ESMTP; 18 Dec 2019 13:55:52 -0800 From: Sean Christopherson To: Marc Zyngier , James Hogan , Paul Mackerras , Christian Borntraeger , Janosch Frank , Paolo Bonzini Cc: James Morse , Julien Thierry , Suzuki K Poulose , David Hildenbrand , Cornelia Huck , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-mips@vger.kernel.org, kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Greg Kurz Subject: [PATCH v2 44/45] KVM: Move putting of vcpu->pid to kvm_vcpu_destroy() Date: Wed, 18 Dec 2019 13:55:29 -0800 Message-Id: <20191218215530.2280-45-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191218215530.2280-1-sean.j.christopherson@intel.com> References: <20191218215530.2280-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Move the putting of vcpu->pid to kvm_vcpu_destroy(). vcpu->pid is guaranteed to be NULL when kvm_vcpu_uninit() is called in the error path of kvm_vm_ioctl_create_vcpu(), e.g. it is explicitly nullified by kvm_vcpu_init() and is only changed by KVM_RUN. No functional change intended. Acked-by: Christoffer Dall Signed-off-by: Sean Christopherson --- virt/kvm/kvm_main.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 21533a472ead..6912d81ca32d 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -352,12 +352,6 @@ static int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id) static void kvm_vcpu_uninit(struct kvm_vcpu *vcpu) { - /* - * no need for rcu_read_lock as VCPU_RUN is the only place that - * will change the vcpu->pid pointer and on uninit all file - * descriptors are already gone. - */ - put_pid(rcu_dereference_protected(vcpu->pid, 1)); free_page((unsigned long)vcpu->run); } @@ -365,6 +359,13 @@ void kvm_vcpu_destroy(struct kvm_vcpu *vcpu) { kvm_arch_vcpu_destroy(vcpu); + /* + * No need for rcu_read_lock as VCPU_RUN is the only place that changes + * the vcpu->pid pointer, and at destruction time all file descriptors + * are already gone. + */ + put_pid(rcu_dereference_protected(vcpu->pid, 1)); + kvm_vcpu_uninit(vcpu); kmem_cache_free(kvm_vcpu_cache, vcpu); } -- 2.24.1