Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752048AbZIVTaq (ORCPT ); Tue, 22 Sep 2009 15:30:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751825AbZIVTap (ORCPT ); Tue, 22 Sep 2009 15:30:45 -0400 Received: from smtp-outbound-2.vmware.com ([65.115.85.73]:41299 "EHLO smtp-outbound-2.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751941AbZIVTal (ORCPT ); Tue, 22 Sep 2009 15:30:41 -0400 Subject: Re: Paravirtualization on VMware's Platform [VMI]. From: Alok Kataria Reply-To: akataria@vmware.com To: Ingo Molnar Cc: Thomas Gleixner , "H. Peter Anvin" , the arch/x86 maintainers , LKML , Jeremy Fitzhardinge , Chris Wright , Rusty Russell , "virtualization@lists.osdl.org" , Greg KH , Linus Torvalds , Andrew Morton In-Reply-To: <20090920074247.GA5733@elte.hu> References: <1253233028.19731.63.camel@ank32.eng.vmware.com> <20090919224430.GB9567@kroah.com> <1253419185.3253.21.camel@ank32.eng.vmware.com> <20090920074247.GA5733@elte.hu> Content-Type: text/plain Organization: VMware INC. Date: Tue, 22 Sep 2009 12:30:45 -0700 Message-Id: <1253647845.10565.20.camel@ank32.eng.vmware.com> Mime-Version: 1.0 X-Mailer: Evolution 2.12.3 (2.12.3-8.el5_2.3) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3961 Lines: 108 Hi Ingo, On Sun, 2009-09-20 at 00:42 -0700, Ingo Molnar wrote: > > The thing is, the overwhelming majority of vmware users dont benefit > from hardware features like nested page tables yet. So this needs to be > done _way_ more carefully, with a proper sunset period of a couple of > kernel cycles. I am fine with that too. Below is a patch which adds notes in feature-removal-schedule.txt, I have marked it for removal from 2.6.34. Please consider this patch for 2.6.32. > If we were able to rip out all (or most) of paravirt from arch/x86 it > would be tempting for other technical reasons - but the patch above is > well localized. We can certainly look at removing some paravirt-hooks which are only used by VMI. Not sure if there are any but will take a look when we actually remove VMI. Thanks, Alok -- Mark VMI for deprecation in feature-removal-schedule.txt. From: Alok N Kataria Add text in feature-removal.txt and also modify Kconfig to disable vmi by default. Patch on top of tip/master. Details about VMware's plan about retiring VMI can be found here http://blogs.vmware.com/guestosguide/2009/09/vmi-retirement.html --- Documentation/feature-removal-schedule.txt | 24 ++++++++++++++++++++++++ arch/x86/Kconfig | 8 +++++--- 2 files changed, 29 insertions(+), 3 deletions(-) diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index fa75220..b985328 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -459,3 +459,27 @@ Why: OSS sound_core grabs all legacy minors (0-255) of SOUND_MAJOR will also allow making ALSA OSS emulation independent of sound_core. The dependency will be broken then too. Who: Tejun Heo + +---------------------------- + +What: Support for VMware's guest paravirtuliazation technique [VMI] will be + dropped. +When: 2.6.34 +Why: With the recent innovations in CPU hardware acceleration technologies + from Intel and AMD, VMware ran a few experiments to compare these + techniques to guest paravirtulization technique on VMware's platform. + These hardware assisted virtualization techniques have outperformed the + performance benefits provided by VMI in most of the workloads. VMware + expects that these hardware features will be ubiquitous in a couple of + years, as a result, VMware has started a phased retirement of this + feature from the hypervisor. We will be removing this feature from the + Kernel too, in a couple of releases. + Please note that VMI has always been an optimization and non-VMI kernels + still work fine on VMware's platform. + + For more details about VMI retirement take a look at this, + http://blogs.vmware.com/guestosguide/2009/09/vmi-retirement.html + +Who: Alok N Kataria + +---------------------------- diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index e214f45..1f3e156 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -485,14 +485,16 @@ if PARAVIRT_GUEST source "arch/x86/xen/Kconfig" config VMI - bool "VMI Guest support" - select PARAVIRT - depends on X86_32 + bool "VMI Guest support [will be deprecated soon]" + default n + depends on X86_32 && PARAVIRT ---help--- VMI provides a paravirtualized interface to the VMware ESX server (it could be used by other hypervisors in theory too, but is not at the moment), by linking the kernel to a GPL-ed ROM module provided by the hypervisor. + VMware has started a phased retirement of this feature from there + products. Please see feature-removal-schedule.txt for details. config KVM_CLOCK bool "KVM paravirtualized clock" -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/