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, URIBL_BLOCKED,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 5B134CA9EB7 for ; Tue, 22 Oct 2019 02:00:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 30F0E21929 for ; Tue, 22 Oct 2019 02:00:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387779AbfJVCAF (ORCPT ); Mon, 21 Oct 2019 22:00:05 -0400 Received: from mga14.intel.com ([192.55.52.115]:61609 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387621AbfJVCAF (ORCPT ); Mon, 21 Oct 2019 22:00:05 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Oct 2019 19:00:05 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,325,1566889200"; d="scan'208";a="196293988" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.41]) by fmsmga008.fm.intel.com with ESMTP; 21 Oct 2019 19:00:03 -0700 From: Sean Christopherson To: Marc Zyngier , James Hogan , Paul Mackerras , Christian Borntraeger , Janosch Frank , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= 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 Subject: [PATCH 44/45] KVM: Move putting of vcpu->pid to kvm_vcpu_destroy() Date: Mon, 21 Oct 2019 18:59:24 -0700 Message-Id: <20191022015925.31916-45-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20191022015925.31916-1-sean.j.christopherson@intel.com> References: <20191022015925.31916-1-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 explicit nullified by kvm_vcpu_init() and is only changed by KVM_RUN. No functional change intended. 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 b1f4ee9c2c76..c079b22032fa 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -318,12 +318,6 @@ 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); } @@ -331,6 +325,13 @@ 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); } -- 2.22.0