From nobody Fri Apr 10 20:21:49 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D72B4ECAAD4 for ; Tue, 30 Aug 2022 12:03:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230429AbiH3MD1 (ORCPT ); Tue, 30 Aug 2022 08:03:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39670 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229756AbiH3MCg (ORCPT ); Tue, 30 Aug 2022 08:02:36 -0400 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F4B2EF9D8; Tue, 30 Aug 2022 05:02:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1661860928; x=1693396928; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=eeD6WJYKHUyfZ/PXC4poyF6VyKFe0V4LAqKVsAEhnLI=; b=CSqQfYURJd8rkqxNgLXcQ2YySp2cJZ49YZsXvGQmTFM47UqF307o167C M2AIfIJ/pzLxJek3sDX3iPRlkxmtgL+sIM9BEPH64jl9u5ceeAs/ASjxg EkqHM6eyfxM0cGi2PHkgZhD4tyb86Ncd4AmetbaeheQWTnEn3Kea/wJkl cCRUjXbpCocUB7kZEcz3VwxhptAomNQillKi/ZEw/wsR/dGITbodYYnup tBJcCOj2zchOhjndqlsFXQZM8eDzqC9S1hQLsXr1jDeuaR+wGTb+u7YcB wp3o83Y4AZjiNJp0Mnkkl06v0GnvaI0mO3fkPRXB9GViL0tIbGaxjSxNz Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10454"; a="356871006" X-IronPort-AV: E=Sophos;i="5.93,274,1654585200"; d="scan'208";a="356871006" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2022 05:02:01 -0700 X-IronPort-AV: E=Sophos;i="5.93,274,1654585200"; d="scan'208";a="787469680" Received: from ls.sc.intel.com (HELO localhost) ([143.183.96.54]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2022 05:02:01 -0700 From: isaku.yamahata@intel.com To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Paolo Bonzini , Sean Christopherson , Kai Huang , Chao Gao , Will Deacon Subject: [PATCH v2 19/19] RFC: KVM: Remove cpus_hardware_enabled and related sanity check Date: Tue, 30 Aug 2022 05:01:34 -0700 Message-Id: <21b2efeb4b43605a8c1a327a3656650d96be0968.1661860550.git.isaku.yamahata@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Isaku Yamahata cpus_hardware_enabled mask seems incomplete protection against other kernel component using CPU virtualization feature. Because it's obscure and incomplete, remove the check. Signed-off-by: Isaku Yamahata --- virt/kvm/kvm_arch.c | 16 ++-------------- 1 file changed, 2 insertions(+), 14 deletions(-) diff --git a/virt/kvm/kvm_arch.c b/virt/kvm/kvm_arch.c index 8f2d920a2a8f..cbad0181c177 100644 --- a/virt/kvm/kvm_arch.c +++ b/virt/kvm/kvm_arch.c @@ -12,22 +12,16 @@ =20 #include =20 -static cpumask_t cpus_hardware_enabled =3D CPU_MASK_NONE; - static int __hardware_enable(void) { - int cpu =3D raw_smp_processor_id(); int r; =20 WARN_ON_ONCE(preemptible()); =20 - if (cpumask_test_cpu(cpu, &cpus_hardware_enabled)) - return 0; r =3D kvm_arch_hardware_enable(); if (r) - pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu); - else - cpumask_set_cpu(cpu, &cpus_hardware_enabled); + pr_info("kvm: enabling virtualization on CPU%d failed\n", + smp_processor_id()); return r; } =20 @@ -41,13 +35,7 @@ static void hardware_enable(void *arg) =20 static void hardware_disable(void *junk) { - int cpu =3D raw_smp_processor_id(); - WARN_ON_ONCE(preemptible()); - - if (!cpumask_test_cpu(cpu, &cpus_hardware_enabled)) - return; - cpumask_clear_cpu(cpu, &cpus_hardware_enabled); kvm_arch_hardware_disable(); } =20 --=20 2.25.1