From patchwork Tue Jun 1 11:12:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zenghui Yu X-Patchwork-Id: 451910 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 422A4C47080 for ; Tue, 1 Jun 2021 11:13:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 235A160232 for ; Tue, 1 Jun 2021 11:13:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233632AbhFALOo (ORCPT ); Tue, 1 Jun 2021 07:14:44 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:6113 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233556AbhFALOn (ORCPT ); Tue, 1 Jun 2021 07:14:43 -0400 Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4FvTw90gBQzYmrR; Tue, 1 Jun 2021 19:10:17 +0800 (CST) Received: from dggema764-chm.china.huawei.com (10.1.198.206) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2176.2; Tue, 1 Jun 2021 19:13:00 +0800 Received: from DESKTOP-8RFUVS3.china.huawei.com (10.174.185.179) by dggema764-chm.china.huawei.com (10.1.198.206) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Tue, 1 Jun 2021 19:13:00 +0800 From: Zenghui Yu To: , CC: , , , , , Subject: [PATCH stable-5.12.y backport 2/2] KVM: arm64: Resolve all pending PC updates before immediate exit Date: Tue, 1 Jun 2021 19:12:38 +0800 Message-ID: <20210601111238.1059-3-yuzenghui@huawei.com> X-Mailer: git-send-email 2.23.0.windows.1 In-Reply-To: <20210601111238.1059-1-yuzenghui@huawei.com> References: <20210601111238.1059-1-yuzenghui@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.185.179] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggema764-chm.china.huawei.com (10.1.198.206) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org commit e3e880bb1518eb10a4b4bb4344ed614d6856f190 upstream. Commit 26778aaa134a ("KVM: arm64: Commit pending PC adjustemnts before returning to userspace") fixed the PC updating issue by forcing an explicit synchronisation of the exception state on vcpu exit to userspace. However, we forgot to take into account the case where immediate_exit is set by userspace and KVM_RUN will exit immediately. Fix it by resolving all pending PC updates before returning to userspace. Since __kvm_adjust_pc() relies on a loaded vcpu context, I moved the immediate_exit checking right after vcpu_load(). We will get some overhead if immediate_exit is true (which should hopefully be rare). Fixes: 26778aaa134a ("KVM: arm64: Commit pending PC adjustemnts before returning to userspace") Signed-off-by: Zenghui Yu Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20210526141831.1662-1-yuzenghui@huawei.com Cc: stable@vger.kernel.org # 5.11 Reviewed-by: Marc Zyngier --- arch/arm64/kvm/arm.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index c18740a1e541..7730b81aad6d 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -715,11 +715,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) return ret; } - if (run->immediate_exit) - return -EINTR; - vcpu_load(vcpu); + if (run->immediate_exit) { + ret = -EINTR; + goto out; + } + kvm_sigset_activate(vcpu); ret = 1; @@ -892,6 +894,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) kvm_sigset_deactivate(vcpu); +out: /* * In the unlikely event that we are returning to userspace * with pending exceptions or PC adjustment, commit these