From patchwork Tue Oct 22 01:59:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 11203649 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 56D0F13BD for ; Tue, 22 Oct 2019 02:12:14 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 34DA02086D for ; Tue, 22 Oct 2019 02:12:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="uSjg34HN" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 34DA02086D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=YIYSruzcIscVW1IBg04VBApFnvjdPGOQ/eJF3TgbFVs=; b=uSjg34HNlEaHrO yUD7dVNI12lfdfiZCk3qmicjqG9zsJl+7PW3qCSCJ8yFiFGMyhJWnq5F+YgjvMqDSoduYy62ftvDZ xzsjQwozFQEkZYZqG3zm0nZMW0Ww6cd8er88qKcHSsupBj3uWNoZnhoppeo4798Qxz59xB3DE8zf6 KBBbxSDtaTmhPVKCgyn4Al9225ySqXtA7W4tYsYfzoNUtTFsa40lih3OeuL63YDtm+/Aj5VJQeZX/ dAvrhdMj/nbswc6bJyVT1lxxE+ydLzzsq4VO5oZi99BOU73YOmR+cDQYamS0mZi1l7Ifisw9PaYUs VPhDzvGRUrMl/CL/2+gg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iMjee-0002DQ-BM; Tue, 22 Oct 2019 02:12:12 +0000 Received: from mga07.intel.com ([134.134.136.100]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iMjT6-0003sV-NW for linux-arm-kernel@lists.infradead.org; Tue, 22 Oct 2019 02:00:19 +0000 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Oct 2019 19:00:04 -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?b?UmFkaW0gS3LEjW3DocWZ?= 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191021_190016_877074_7F56DB7C X-CRM114-Status: GOOD ( 13.14 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [134.134.136.100 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kvm-ppc@vger.kernel.org, Wanpeng Li , kvm@vger.kernel.org, David Hildenbrand , Joerg Roedel , Cornelia Huck , linux-mips@vger.kernel.org, Sean Christopherson , linux-kernel@vger.kernel.org, James Morse , linux-arm-kernel@lists.infradead.org, Vitaly Kuznetsov , Suzuki K Poulose , kvmarm@lists.cs.columbia.edu, Julien Thierry , Jim Mattson Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.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); }