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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 67F78C2B9F6 for ; Mon, 17 May 2021 15:45:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 45822611EE for ; Mon, 17 May 2021 15:45:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344683AbhEQPp1 (ORCPT ); Mon, 17 May 2021 11:45:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:53306 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245497AbhEQP3u (ORCPT ); Mon, 17 May 2021 11:29:50 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 03AE7613F5; Mon, 17 May 2021 14:37:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621262258; bh=2ZG0b9EVKtAyzoHzd47jQfWhZOI9s3h/S+m0CpotFg4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ao4riwsHDtJizCzo3beXqJMkN75fANOOW+APbpsnpgWg8XWTn0QRD7HLr+NMzDyi1 Iey2l6gT7eCNiHpVPBWh83pkCdsTB4yjLqinD+U/iPT89cC7dZEqpFXrtykbUnQd4K kxJoqs9i7HBaU5X0hrFDnsv7FOsKyw1DMgrS12rM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sean Christopherson , Wanpeng Li , Paolo Bonzini , Sasha Levin Subject: [PATCH 5.11 251/329] KVM: LAPIC: Accurately guarantee busy wait for timer to expire when using hv_timer Date: Mon, 17 May 2021 16:02:42 +0200 Message-Id: <20210517140310.597532327@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210517140302.043055203@linuxfoundation.org> References: <20210517140302.043055203@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wanpeng Li [ Upstream commit d981dd15498b188636ec5a7d8ad485e650f63d8d ] Commit ee66e453db13d (KVM: lapic: Busy wait for timer to expire when using hv_timer) tries to set ktime->expired_tscdeadline by checking ktime->hv_timer_in_use since lapic timer oneshot/periodic modes which are emulated by vmx preemption timer also get advanced, they leverage the same vmx preemption timer logic with tsc-deadline mode. However, ktime->hv_timer_in_use is cleared before apic_timer_expired() handling, let's delay this clearing in preemption-disabled region. Fixes: ee66e453db13d ("KVM: lapic: Busy wait for timer to expire when using hv_timer") Reviewed-by: Sean Christopherson Signed-off-by: Wanpeng Li Message-Id: <1619608082-4187-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin --- arch/x86/kvm/lapic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 570fa298083c..70eb00f4317f 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1908,8 +1908,8 @@ void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu) if (!apic->lapic_timer.hv_timer_in_use) goto out; WARN_ON(rcuwait_active(&vcpu->wait)); - cancel_hv_timer(apic); apic_timer_expired(apic, false); + cancel_hv_timer(apic); if (apic_lvtt_period(apic) && apic->lapic_timer.period) { advance_periodic_target_expiration(apic); -- 2.30.2