From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ADA52C74A4B for ; Thu, 11 Jul 2019 08:05:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A59C208E4 for ; Thu, 11 Jul 2019 08:05:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="e5RJGnpl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728072AbfGKIF5 (ORCPT ); Thu, 11 Jul 2019 04:05:57 -0400 Received: from merlin.infradead.org ([205.233.59.134]:53644 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727796AbfGKIF4 (ORCPT ); Thu, 11 Jul 2019 04:05:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=IPSfomtHuYyD/Zm6ExVXi3c9MiHEqn+oFR7ETfQXE8M=; b=e5RJGnpl7j6oc/4VSLR5nJVa9 c/ZF/bgP61ILWcoNuoMDymxMTIaY07CGbTLk8z467Zxpmds5Zl3h1dVYOa3+WXeWBtICyinPLKZjL BbyV/m8R1Bk8SKx4Zwn94yh0LDPo9mYR0Sn87NuGb2m+ZgVXUJHSNbnME3Puy/eTG/FN2iNetIMl4 6dfcSHPw5slwHAqBLI6MvvIhcLKKkT5Impu+AsoGl2oypNWehWymheAfsDpgmwX7PWGNxElNpQUMp rHSVEQtg0p8sQxtoJOyLqxXzvb2VFL/8qggqJ+ljjPX5t/To8kXKq0kulUN97RblP2CRgm22Sn5tJ H+y08PQBQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hlU4s-0002Nn-Nv; Thu, 11 Jul 2019 08:05:19 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 7906120213043; Thu, 11 Jul 2019 10:05:17 +0200 (CEST) Date: Thu, 11 Jul 2019 10:05:17 +0200 From: Peter Zijlstra To: Steven Rostedt Cc: tglx@linutronix.de, bp@alien8.de, mingo@kernel.org, luto@kernel.org, torvalds@linux-foundation.org, hpa@zytor.com, dave.hansen@linux.intel.com, jgross@suse.com, linux-kernel@vger.kernel.org, zhe.he@windriver.com, joel@joelfernandes.org, devel@etsukata.com Subject: Re: [PATCH v2 6/7] x86/entry/64: Remove TRACE_IRQS_*_DEBUG Message-ID: <20190711080517.GU3402@hirez.programming.kicks-ass.net> References: <20190704195555.580363209@infradead.org> <20190704200050.591915266@infradead.org> <20190710232456.5f2de961@oasis.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190710232456.5f2de961@oasis.local.home> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 10, 2019 at 11:24:56PM -0400, Steven Rostedt wrote: > On Thu, 04 Jul 2019 21:56:01 +0200 > Peter Zijlstra wrote: > > > Since INT3/#BP no longer runs on an IST, this workaround is no longer > > required. > > > > Tested by running lockdep+ftrace as described in the initial commit: > > > > 5963e317b1e9 ("ftrace/x86: Do not change stacks in DEBUG when calling lockdep") > > It looks like a clean revert, and it passed my ftrace smoke tests with > lockdep enabled (although I triggered a locked warning unrelated to > this, with the text_mutex and module_mutex, but I'm hoping my tree has > the fixes for that). > > Reviewed-by: Steven Rostedt (VMware) Thanks! > Hmm, does this mean we can remove the IDT switching in the NMI handler > as well? I'll have to go look at that; there still are ISTs and NMIs can still hit those.