Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752399AbaKUTrG (ORCPT ); Fri, 21 Nov 2014 14:47:06 -0500 Received: from mail-qc0-f179.google.com ([209.85.216.179]:52977 "EHLO mail-qc0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752368AbaKUTq7 (ORCPT ); Fri, 21 Nov 2014 14:46:59 -0500 MIME-Version: 1.0 In-Reply-To: References: <20141120221122.GA25393@htj.dyndns.org> <20141120230514.GB25393@htj.dyndns.org> <20141120233920.GC25393@htj.dyndns.org> <20141121162742.GB15461@htj.dyndns.org> <20141121170805.GD30603@home.goodmis.org> <20141121142301.564f7eb7@gandalf.local.home> Date: Fri, 21 Nov 2014 11:46:57 -0800 X-Google-Sender-Auth: Vzv1yDKP23nAW_2NAL-TPwu09Jk Message-ID: Subject: Re: frequent lockups in 3.18rc4 From: Linus Torvalds To: Steven Rostedt Cc: Andy Lutomirski , Tejun Heo , "linux-kernel@vger.kernel.org" , Thomas Gleixner , Arnaldo Carvalho de Melo , Peter Zijlstra , Frederic Weisbecker , Don Zickus , Dave Jones , "the arch/x86 maintainers" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 21, 2014 at 11:34 AM, Linus Torvalds wrote: > > So I kind of agree, but it wouldn't be my primary worry. My primary > worry is actually paravirt doing something insane. Btw, on that tangent, does anybody actually care about paravirt any more? I'd love to start moving away from it. It makes a lot of the low-level code completely impossible to follow due to the random indirection through "native" vs "paravirt op table". Not just the page table handling, it's all over. Anybody who seriously does virtualization uses hw virtualization that is much better than it used to be. And the non-serious users aren't that performance-sensitive by definition. I note that the Fedora kernel config seems to include paravirt by default, so you get a lot of the crazy overheads.. Linus -- 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/