From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:37784 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755941AbcDLONc (ORCPT ); Tue, 12 Apr 2016 10:13:32 -0400 Date: Tue, 12 Apr 2016 07:13:13 -0700 From: Greg Kroah-Hartman To: Radim =?utf-8?B?S3LEjW3DocWZ?= Cc: Ben Hutchings , Yuki Shibuya , Paolo Bonzini , stable Subject: Re: [PATCH 4.5 007/238] KVM: i8254: change PIT discard tick policy Message-ID: <20160412141313.GA7996@kroah.com> References: <1460417015.25201.67.camel@decadent.org.uk> <20160412012135.GA11311@kroah.com> <20160412133023.GA3696@potion.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20160412133023.GA3696@potion.brq.redhat.com> Sender: stable-owner@vger.kernel.org List-ID: On Tue, Apr 12, 2016 at 03:30:23PM +0200, Radim Krčmář wrote: > 2016-04-11 18:21-0700, Greg Kroah-Hartman: > > On Tue, Apr 12, 2016 at 12:23:35AM +0100, Ben Hutchings wrote: > > > On Wed, 2016-03-02 at 22:56 +0100, Radim Krčmář wrote: > >> > Even though there is a chance of regressions, I think we can fix the > >> > LVT0 NMI bug without introducing a new tick policy. > >> [...] > >> > >> Given the 'chance of regressions', should we let this sit in mainline > >> longer before including it in stable updates? > > > > Hm, good point, Radim, what do you think, is this good to go to stable > > now? This has been in since 4.6-rc1, so it's been a few weeks with > > people running it already... > > I think it is good to go. No reasonable workload should regress and the > fixed use-case is common on old linux guest. > > This patch makes a difference if the guest doesn't EOI in PIT interrupts > before the next one arrives. PIT would have been unreliable in that > situation, so all worloads that that could regress have likely been > avoided. Changes to NMI injection would need even crazier guest to > regress. Ok, thanks, leaving it in. greg k-h