Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756509AbbBHRsf (ORCPT ); Sun, 8 Feb 2015 12:48:35 -0500 Received: from e23smtp04.au.ibm.com ([202.81.31.146]:40288 "EHLO e23smtp04.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753826AbbBHRsd (ORCPT ); Sun, 8 Feb 2015 12:48:33 -0500 Message-ID: <54D7A1AD.3050108@linux.vnet.ibm.com> Date: Sun, 08 Feb 2015 23:19:33 +0530 From: Raghavendra K T Organization: IBM User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130625 Thunderbird/17.0.7 MIME-Version: 1.0 To: Linus Torvalds CC: Thomas Gleixner , Ingo Molnar , Peter Anvin , Peter Zijlstra , Konrad Rzeszutek Wilk , Paolo Bonzini , Paul McKenney , Waiman Long , Dave Jones , Oleg Nesterov , the arch/x86 maintainers , Jeremy Fitzhardinge , Paul Gortmaker , Andi Kleen , Jason Wang , Linux Kernel Mailing List , KVM list , virtualization , xen-devel@lists.xenproject.org, Rik van Riel , Christian Borntraeger , Andrew Morton , Andrey Ryabinin , Sasha Levin Subject: Re: [PATCH] x86 spinlock: Fix memory corruption on completing completions References: <1423234148-13886-1-git-send-email-raghavendra.kt@linux.vnet.ibm.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15020817-0013-0000-0000-000000C9635F Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1305 Lines: 33 On 02/06/2015 09:55 PM, Linus Torvalds wrote: > On Fri, Feb 6, 2015 at 6:49 AM, Raghavendra K T > wrote: >> Paravirt spinlock clears slowpath flag after doing unlock. > [ fix edited out ] > > So I'm not going to be applying this for 3.19, because it's much too > late and the patch is too scary. Plus the bug probably effectively > never shows up in real life (it is probably easy to trigger the > speculative *read* but probably never the actual speculative write > after dropping the lock last). > Understood and agreed. > This will need a lot of testing by the paravirt people - both > performance and correctness. So *maybe* for 3.20, but maybe for even > later, and then marked for stable, of course. > > Are there any good paravirt stress-tests that people could run for > extended times? > I have been running several benchmarks (kern, sys, hack, ebizzy etc in in 1x,2x scenarios. I run them for performance test as well. (In the current patch I did not get kvm hang in normal run, But overcommit reproduced it). -- 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/