Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933209AbdGKOlP (ORCPT ); Tue, 11 Jul 2017 10:41:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:39182 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932653AbdGKOlN (ORCPT ); Tue, 11 Jul 2017 10:41:13 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8C32622C9F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=luto@kernel.org MIME-Version: 1.0 In-Reply-To: References: <1476188240-3502-1-git-send-email-wanpeng.li@hotmail.com> From: Andy Lutomirski Date: Tue, 11 Jul 2017 07:40:50 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH RFC 0/2] KVM: x86: Support using the VMX preemption timer for APIC Timer periodic/oneshot mode To: Wanpeng Li Cc: Andy Lutomirski , "linux-kernel@vger.kernel.org" , kvm , Thomas Gleixner , X86 ML , Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Yunhong Jiang , Wanpeng Li Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 478 Lines: 12 On Mon, Jul 10, 2017 at 7:43 PM, Wanpeng Li wrote: > > Sigh, I heard the same idea from a company called Huawei, they applied > the patent for the idea. Seriously? What arseholes. Also, calling that an invention is a bit of a joke. It's called the VMX *preemption* timer. Using it for preemption isn't exactly rocket science. Neither is passing an MSR straight through. That being said, the lack of scaling and offset support is indeed problematic.