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=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,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 B975BC433E1 for ; Mon, 17 Aug 2020 05:57:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9CC1D206DA for ; Mon, 17 Aug 2020 05:57:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726591AbgHQF5z (ORCPT ); Mon, 17 Aug 2020 01:57:55 -0400 Received: from out30-130.freemail.mail.aliyun.com ([115.124.30.130]:37592 "EHLO out30-130.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726235AbgHQF5y (ORCPT ); Mon, 17 Aug 2020 01:57:54 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R171e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01f04397;MF=zelin.deng@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0U5z1wNG_1597643859; Received: from localhost(mailfrom:zelin.deng@linux.alibaba.com fp:SMTPD_---0U5z1wNG_1597643859) by smtp.aliyun-inc.com(127.0.0.1); Mon, 17 Aug 2020 13:57:39 +0800 From: Zelin Deng To: Paolo Bonzini , Thomas Gleixner Cc: Brijesh Singh , Artie Ding , Caspar Zhang , Zelin Deng , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] KVM: x86: kvmclock_init_mem() should be called any way Date: Mon, 17 Aug 2020 13:57:39 +0800 Message-Id: <20200817055739.9994-1-zelin.deng@linux.alibaba.com> X-Mailer: git-send-email 2.20.1.2432.ga663e714 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org pvclock data pointers of vCPUs >= HVC_BOOT_ARRAY_SIZE (64) are stored in hvclock_mem wihch is initialized in kvmclock_init_mem(). Here're 3 scenarios in current implementation: - no-kvmclock is set in cmdline. kvm pv clock driver is disabled, no impact. - no-kvmclock-vsyscall is set in cmdline. kvmclock_init_mem() won't be called. No memory for storing pvclock data of vCPUs >= 64, vCPUs >= 64 can not be online or hotpluged. - tsc unstable. kvmclock_init_mem() won't be called. vCPUs >= 64 can not be online or hotpluged. It's not reasonable that vCPUs hotplug have been impacted by last 2 scenarios. Hence move kvmclock_init_mem() to front, in case hvclock_mem can not be initialized unexpectedly. Fixes: 6a1cac56f41f9 (x86/kvm: Use __bss_decrypted attribute in shared variables) Signed-off-by: Zelin Deng --- arch/x86/kernel/kvmclock.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 34b18f6eeb2c..1abbda25e037 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -271,7 +271,14 @@ static int __init kvm_setup_vsyscall_timeinfo(void) { #ifdef CONFIG_X86_64 u8 flags; +#endif + + if (!kvmclock) + return 0; + + kvmclock_init_mem(); +#ifdef CONFIG_X86_64 if (!per_cpu(hv_clock_per_cpu, 0) || !kvmclock_vsyscall) return 0; @@ -282,8 +289,6 @@ static int __init kvm_setup_vsyscall_timeinfo(void) kvm_clock.vdso_clock_mode = VDSO_CLOCKMODE_PVCLOCK; #endif - kvmclock_init_mem(); - return 0; } early_initcall(kvm_setup_vsyscall_timeinfo); -- 2.20.1